The  Enemy  Submarine 


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BULLETIN    NO.    2 
May  1,  1918 

Information  of  oonstmction, 
methods  of  attack,  the  tor- 
pedo and  its  actions  anA 
ntethods  proposed  for  d«> 
fensive  and  offensive  pro- 
teetion. 


COMPILKU     BY    THK 


C        J  NAVAL  CONSULTING  BOARD 


U 


WAR  COMMITTEE  OF  TECHNICAL  SOCIETIES 
FROM 

Ifli^nBation  Already  Published  and  Oth^r 
Recently  Released. 


■xaawaed  and  publication  authorized. 


9emmMamy  at  the  'Ntt'v^. 


NATAL    CONSULTING   BOABJ> 

OF   THE    UNITED    STATES 

OFFICE  OF  THE  SECRBTART 

18    PARK   ROW,    NEW  YORK_ 


THE  LIBRARY 

OF 

THE  UNIVERSITY 

OF  CALIFORNIA 

LOS  ANGELES 

From  the  Library  of 
Neil  Arthur  Getz 


TABUS  OF  CONTBNTS. 

"Foreword     5 

Experiments  and  Development     6 
Reasons  for  Rejectioa  of  Many  Proposals     7 


The 
Submarine 

and  its 
Operation 


-History     9 


Types 


FROM  THE  LIBRARY 

OF 
NEIL  ARTHUR  GETZ 


C Modem  Types     10 
"One-Man"  Type     10 
Submarines  Cairied  by  Motherships      1 1 


Construction      


Equipaeat        


GHuIl  Construction  1 1 
Source  of  Power  12 
Speed      12 

Listening  Devices      13 
Periscopes     1 5 
Torpedoes     17 
Mines     1 7 
Guns     1 7 
Wireless     17 
Net-cutting  Devices,  etc      17 


The 

Enemy — 
Submarine 


Protection 

of 

Voyaging 

Ships 


Offensive 

Against    

Submarines 


Methods  I Bases      1 7 

of  Maneuvering      18 

Offense  I Method  of  Attack      18 

I Detecting  the  Presence  of  a  Submarine     20 

Nets,  Screens,  Guards,  etc.     20 

Decreasing  the  Visibility  of  Vessels     22 

Speed  of  Vessel     24 

Special  Ship  Construction     24 
Convoying     26 

r Confining  to  Bases     26 


Means  of 
Discovery 


-Nete     26 

Trawling     27 

Aircraft     27 

Optical  Detection     28 

Wake  of  Submarine  and  Torpedo 
-Seeing  Under  Water     28 


26 


Patrol  for  Submarines     29 
Submarines  Used  Against  Submarines 


29 


Destruction 

of 
Submarines 


30 


I Gunfire     30 

Depth  Charges     30 

Bombing  Hydro-aeroplanes 

Nests  of  Torpedoes     3 1 

Towing  mines     31 
^—Torpedoes  Influenced  by  Souad     31 


33 


Torf)edoes     3 1 

Stationary  Mines     33 

Mmes   Floating  Mines     33 

Contact  Depth  Mines 

Refereace*  on  the  Submarine  and  Kindred  Problems     34 

C Committee  of  Elxaminers     47 
Naval  Consulting  Board  of  the  United  Stites 
War  Committee  of  Technical  Socteiies     46 


48 


Digitized  by  the  Internet  Archive 

in  2007  with  funding  from 

IVIicrosoft  Corporation 


http://www.archive.org/details/enemysubmarineOOunitiala 


FOREWORD. 

This  Bulletin  is  prepared  to  supersede  Bulletin  No.  1, 
"The  Submarine  and  Kindred  Problems,"  issued  on  July 
14th,  1917,  by  the  Naval  Consulting  Board;  to  indicate 
more  fully  the  requirements  for  war  inventions ;  to  state 
the  limitations  outside  of  which  creative  effort  may  not 
be  expected  to  produce  results  of  value  and  to  assist  the 
student  in  avoiding  the  duplication  of  previous  accom- 
piishment.  It  is  also  intended  to  give  wide  publicity  to 
certain  general  information  already  well  known  to  the 
enemy,  in  order  that  the  difficulties  in  overcoming  the 
German  submarine  may  be  understood. 

References  from  which  detailed  information  in  rela- 
tion to  submarine  problems  may  be  obtained,  and  a  list 
of  references  with  extracts  in  relation  to  submarine 
strategy  and  tactics,  are  included. 

The  Naval  Consulting  Board  is  acting  officially  as  a 
national  board  of  inventions  and  is  conducting  its  work 
with  the  active  cooperation  of  the  War  Committee  of 
Technical  Societies. 

By  means  of  the  condensed  information  contained  in 
Bulletins,  it  is  hoped  that  inventors  and  others  who  wish 
to  present  matters  for  examination  will  be  enabled  first 
to  analyze  their  own  inventions.  By  this  help,  the  ex- 
aminers can  devote  a  large  part  of  their  time  to  the  de- 
velopment of  inventions,  plans,  or  devices  which  give 
promise  of  assisting  the  Government  in  prosecuting  the 
war. 


EXPERIMENTS  AND  DEVELOPMENT. 

The  Army  and  Navy  and  the  various  civilian  urgani- 
zations  cooperating  with  them  are  continually  experi- 
menting with  and  developing  new  ways  and  means  to 
increase  the  effectiveness  of  the  machinery  of  War.  The 
Navy  is  giving  special  attention  to  the  submarine  and 
kindred  problems,  but  for  obvious  reasons  many  of  the 
details  of  this  work  cannot  be  disclosed. 

The  amount  of  time  and  labor  necessary  to  determine 
the  value  of  a  device,  as  compared  with  what  is  already 
in  use,  is  infinitely  greater  than  can  be  appreciated  by 
the  layman  or  even  the  average  engineer.  Few  realize 
the  stress,  hurry  and  lack  of  facilities  in  a  battle.  Any 
delay  or  difficulty  in  the  operation  of  new  devices  in 
action  is  fatal.  For  these  reasons  many  schemes  and  de- 
vices appearing  practicable  and  effective  in  laboratory 
tests  have  to  be  abandoned  when  tried  out  in  service. 
There  is,  therefore,  a  very  wise  reluctance  on  the  part 
of  the  Government  to  undertake  experiments  with,  or 
development  of  proposals  that  appear,  on  preliminary 
examination,  to  be  of  such  a  delicate  or  complex  nature 
that  they  would  probably,  though  perfected,  lack  the 
essentials  of  strength,  ease  of  operation  and  reliability. 

No  proposal  which  involves  premises  not  based  on  the 
laws  of  nature,  as  understood  and  accepted  by  authon- 
ties,  is  entitled  to  be  recommended  for  experiment  and 
development,  unless  the  inventor  shows  that  he  is  thor- 
oughly familiar  with  such  laws  and  can  demonstrate  that 
there  is  a  possibility  of  the  accepted  understanding  be- 
ing erroneous. 

Experiments  and  development  are  unnecessary  in  the 
case  of  devices  which,  though  apparently  operable,  do 
not  promise  greater  efficiency  than  those  already  in  use. 


y 


It  may  be  stated  that  the  inability  of  the  Government 
to  make  use  of  most  of  the  proposals  submitted  is  due  to 
the  fact  that  the  devices  suggested  are  either  already  in 
use,  less  eflficient  than  those  now  employed,  or,  for  good 
reasons,  are  thought  to  be  impracticable  and  open  to  one 
or  more  of  the  objections  mentioned  in  the  list  below: 

1.  It  has  already  been  suggested  and  passed  upon. 

2.  A  similar  device  is  already  in  use. 

3.  A  desideratum,  rather  than  an  invention,  is  offered. 

4.  It  is  not  considered  practicable. 

5.  According  to  the  authorities,  such  a  device  is  not 

required. 

6.  Prevailing  conditions  render  its  use  impossible. 

7.  The  desired  purpose  is  now  more  efficiently  accom- 

plished. 

8.  There  is  no  known  method  of  applying  the  sugges- 

tion. 

9.  Not  practicable  according  to  natural  laws  as  known. 

10.  The  facilities  for  construction  are  not  available. 

11.  It  would  violate  laws  of  war  as  interpreted  by  this 

country  and  its  Allies. 

12.  It  would  be  too  dangerous  to  use. 

13.  A  similar  suggestion  has  been  tried  and  abandoned. 

14.  The  proposal  is  not  fully  understood. 

15.  Its  use  would  interfere  with  handling  a  ship. 

16.  Not  practicable  under  marine  conditions. 

17.  Ineffective  against  submarines  as  now  built. 

18.  Development  in  the  art  has  progressed  beyond  that 

which  is  indicated  by  the  proposal. 

No  proposal  that  is  open  to  any  of  the  foregoing  ob- 
jections will  be  recommended  by  the  examiners. 


Electro- 


Detection 
by  Mag- 
netic 
Needle 


InBaence  on 
Compass 


Many  proposals  which  depend  for  their  operation 
upon  effects  which  are  contrary  to  natural  laws  as  known 
^ve  been  submitted.  Below  is  given  an  outline  of  some 
of  the  most  popular  misconceptions. 

Although  the  laws  governing  the  use  of  electro-mag- 
nets are  generally  known  and  applied  in  a  practical 
manner  in  a  multitude  of  devices  in  common  use,  even 
the  man  of  wide  experience  will  be  astonished  at  the 
limited  range  of  their  effect.  For  instance,  the  magnets 
Msed  in  our  manufacturing  plants,  for  lifting  heavy 
masses  of  iron  or  steel  are  designed  to  exercise  maximum 
magnetic  effect,  and  for  operation  require  a  very  con- 
siderable amount  of  electrical  energy;  yet  a  magnet 
which  can  lift  twenty  tons  when  placed  in  contact  with 
an  iron  plate  of  that  weight,  will  not  lift  two  pounds  of 
iron  or  steel  if  separated  from  it  a  distance  of  two  feet. 
Therefore  proposed  devices  which  depend  on  the  attrac- 
tive power  of  magnets  for  their  operation  in  deflecting 
or  arresting  torpedoes,  mines  or  submarines,  must  be 
governed  by  the  simple  laws  of  magnetism.  A  torpedo 
weighing  approximately  2,500  pounds  and  traveling  at 
a  speed  of  from  25  to  45  miles  an  hour,  will  not  be  de- 
flected to  any  considerable  degree  by  any  known  appli- 
cation of  magnetism;  and  it  is  not  believed  that  an  enemy 
torpedo,  mine  or  submarine  will  ever  be  found  in  a  posi- 
tion to  be  interfered  with  effectively  by  any  electro-mag- 
netic means,  however  powerful. 

Tests  made  on  an  actual  submarine  have  shown  that 
the  magnetic  effects,  due  to  this  mass  of  iron,  are  quite 
limited  in  range.  For  instance,  at  150  feet  distance  the 
magnetic  effect  due  to  a  submarine  is  only  about  1  %  as 
much  as  the  earth's  magnetic  effect. 

The  submarine  is  equipped  with  a  gyroscopic  compass 
that  cannot  be  affected  by  any  magnetic  influence  from 
the  outside. 

'  A  magnet  deriving  its  power  from  any  battery  that 
could  be  contained  within  a  bomb  would  not  be  powerful 
enough  to  hold  the  bomb  in  contact  with  a  boat  running 
through  the  water;  therefore  the  scheme  is  impracticable. 
The  main  point  would  be  to  locate  the  submarine.  ^Vhen 


the  submarine  is  once  located,  very  simple  methods  of 
disposing  of  it  are  at  hand. 

There  is  a  general  misconception  regarding  the  elec-  Electrical 
trification  of  water  and  the  atmosphere.  There  is  no  ^^*<^*» 
known  method  of  charging  the  sea  with  electricity;  of 
shooting  a  bomb  of  electricity,  or  of  charging  the  atmo- 
sphere with  electrocuting  currents.  Suggestions  along 
these  lines  should  show  that  the  writer  has  made  research 
in  the  laws  governing  the  application  of  electrical  en- 
ergy, and  should  contain  sufficient  proof  of  their  feas- 
ibility, to  insure  serious  consideration. 

On  the  other  hand,  applications  of  the  transmission 
of  electrical  energy  by  means  of  alternating  or  pulsat- 
ing currents — as  used  in  wireless  systems,  for  example — 
belong  to  a  different  class  of  electrical  development.  In- 
ventive genius  is  rapidly  improving  apparatus  of  this 
type  for  the  sending  and  receiving  of  signals  and  mes- 
sages, and  the  possibility  of  valuable  results  in  this  field 
is  unlimited. 

THE  SUBMARINE  AND  ITS  OPERATION. 

The  first  recorded  experiment  in  submarine  operation  Histwry 
was  made  by  a  Hollander,  Dr.  Cornelius  Van  Drebbel, 
who  in  1624  constructed  a  one-man  submarine  operated 
by  feathering  oars,  which  made  a  successful  underwater 
trip  from  Westminster  to  Greenwich  on  the  Thames. 

Dr.  David  Bushnell,  an  American  inventor  and  grad- 
uate of  Yale  in  the  class  of  1775,  nearly  sank  the 
"Eagle"  in  New  York  Harbor  during  the  Revolution- 
ary War  by  the  use  of  his  little  one-man-powered  sub- 
marine, the  "American  Turtle." 

In  England,  the  American  inventor,  Robert  Fulton, 
in  the  presence  of  William  Pitt,  then  Chancellor,  and  a 
large  number  of  spectators,  blew  up  a  brig  by  exploding 
a  mine  which  he  had  placed  under  her  bottom  by  the  use 
of  his  submarine  boat.  Both  of  these  inventors  were  dis- 
couraged and  were  refused  the  necessary  assistance  to 
enable  them  to  develop  further  their  ideas  regarding 
submarines,  although  they  had  undoubtedly  shown  that 
there  were  great  possibilities  in  the  underwater  type  of 
vessel. 

9 


Various  unsuccessful  attempts  were  made  to  utilize 
submarines  during  the  Civil  War,  but  at  that  time  their 
only  means  of  offense  was  a  torpedo  on  the  end  of  a  long 
spar,  and  the  solitary  recorded  hit  was  disastrous  to  both 
the  warsliip  and  the  submarine.  Just  as  the  breach-load- 
ing rifle,  a  very  ancient  device,  failed  to  come  into  its 
own  until  the  invention  of  the  metallic  cartridge,  the  sub- 
marine had  to  await  the  invention  of  the  automotive  tor- 
pedo before  it  became  a  really  efficient  means  of  offense. 

Types. 

Modem  submarines  are  divided  into  two  general 
classes :  the  Coast  Defense  type  of  from  300  to  700  tons 
surface  displacement,  and  the  Cruising  type  of  from  800 
to  2,500  tons  displacement,  having  a  radius  of  action  of 
from  3,000  to  8,000  miles  and  capable  of  operating  along 
the  Atlantic  Coast  of  the  United  States  from  European 
bases. 

Germany  appears  to  be  devoting  her  energy  at  pres- 
ent to  the  construction  of  a  small  group  of  a  still  larger 
type,  reported  to  have  a  displacement  of  2,800  tons, 
which  also  possesses  superior  gun  equipment  for  sur- 
face operations,  greater  speed  when  cruising  on  the 
surface,  very  much  more  habitable  quarters  for  the  crew, 
and  storage  capacity  for  a  larger  number  of  torpedoes 
and  other  supplies. 

Many  hundreds  of  proposals  have  been  received  ad- 
vocating one-man  submarines  and  submarines  of  small 
size,  to  he  manufactured  in  great  numbers  for  the  pur- 
pose of  attacking  and  destroying  the  larger  types  of 
enemy  submarines.  This  subject  has  been  given  exhaus- 
tive consideration  and  it  has  been  conclusively  proved 
that  no  small  submarine  can  be  provided  with  the  neces- 
sary power,  speed,  equipment  and  living  quarters  for  the 
crew  to  enable  it  to  operate  successfully  in  the  submarine 
zone.  Even  the  smallest  of  modem  submarines  re- 
quires a  number  of  devices  for  its  successful  operation; 
an  internal  combustion  engine,  an  electric  motor — which 
also  can  be  used  as  a  generator  to  charge  the  storage 

10 


batteries — water  ballast  and  trimming  tanks,  pumps,  air 
compressors,  air  storage  tanks,  torpedo  tubes,  storage 
space  for  torpedoes,  quarters  for  crew,  and  other  ma- 
chinery and  auxiliaries. 

Proposals  to  have  small  submarines  carried  by  mother  Submarines 
battleships  or  merchantmen  and  put  overboard  have  not  Mo*Ser-^^ 
received  favorable  consideration,  because  of  the  practical  Ships 
difficulties  involved  in  launching  and  maintaining  them. 
Although  a  special  type  of  small  submarine  has  been 
designed  with  the  intention  of  having  it  carried  upon  the 
deck  of  a  battleship  and  launched  for  operations  in  the 
immediate  vicinity  of  the  ship,  no  records  of  successful 
tests  are  available.    The  smallest  type  of  modem  coast 
defense  submarines,  which  can  hold  the  necessary  ap- 
paratus to  have  a  useful  range  of  action,  weighs  about 
^00  tons ;  the  handling  of  such  weights  from  the  deck  of 
a  vessel  at  sea  cannot  be  accomplished  with  any  degree 
of  safety. 

Submarines  for  this  purpose  have  been  proposed  many 
times  and  in  some  cases  carefully  designed.  No  really 
successful  design,  however,  has  been  evolved. 

Construction. 

Generally,  the  German  U-boat — ^which  is  the  designa-  Hull  Con- 
tion  for  the  enemy  ocean-going  submarines — is  made  struction 
with  a  double  hull.  The  bottom  space  between  the  inner 
and  outer  hulls  is  used  for  water  ballast;  the  top  spaca 
is  used  for  carrying  fuel  oil.  Water  ballast  displaces 
the  fuel  oil  as  it  is  consumed  by  the  internal  combustion 
engine. 

The  frequent  statements  that  oil  has  been  seen  on  the 
sea,  after  a  U-boat  had  been  attacked,  may  have  merely 
indicated  that  the  submarine's  outer  hull  had  been  punc- 
tured. However,  there  is  some  oil  slick  on  the  surface 
when  the  exhaust  mufflers  are  flooded. 

According  to  recent  statements,  the  conning  tower, 
in  the  latest  type  of  German  submarine,  is  protected  by 
a  thin  belt  of  armor  plate,  and  the  vital  parts  of  the  hull, 
which  are  exposed  when  operating  on  the  surface,  are 
also  made  heavier  than  the  rest  of  the  hull,  to  protect 
them  at  least  from  the  smaller  caliber  guns. 

11 


Even  if  the  periscope  and  conning  tower  are  shot 
away,  the  submarine  may  still  be  able  to  keep  afloat  and 
operate. 
Source  of  The  internal  combustion  oil  engine  of  the  Diesel  or 

Power  Semi-Diesel  type  is  almost  universally  employed  for 

surface  operation  in  modern  submarines,  although  much 
experimenting  has  been  done  with  steam-driven  craft, 
and  many  engineers  believe  that,  for  extremely  high 
power,  steam  may  yet  be  used  effectively  if  some  of  the 
inherent  disadvantages — excessive  heat,  etc. — can  be 
overcome.  The  limit  of  practical  size  has  almost  been 
reached  in  the  internal  combustion  engines  used  in  the 
latest  type  of  submarine,  and  if  more  power  is  needed 
the  engines  themselves  will  have  to  be  improved,  or,  per- 
haps steam  plants  will  be  resorted  to. 

Owing  to  the  fact  that  internal  combustion  engines 
require  a  great  deal  of  air  for  their  operation,  which  is 
not  available  when  a  boat  is  submerged,  submarines  must 
be  equipped  with  an  electric  motor  run  by  storage  bat- 
teries for  underwater  propulsion.  It  is,  therefore,  nec- 
essary, after  the  storage  batteries  are  discharged  by  use, 
for  the  boat  to  come  to  the  surface  while  its  electric  gen- 
erating apparatus,  driven  by  the  internal  combustion  en- 
gine, recharges  the  batteries. 
Speed  The  speed  of  a  submarine,  like  that  of  other  vessels, 

depends  upon  the  power  of  its  engines  or  motors  in  over- 
coming the  resistance  of  the  hull  to  being  driven  through 
the  water.  For  submerged  operations,  the  electric  motor 
operates  the  propeller,  the  engine  being  uncoupled  and 
the  current  for  the  motor  supplied  by  storage  batteries. 
This  electrical  equipment,  if  it  be  of  high  power,  occu- 
pies much  space  and  is  extremely  heavy,  especially  if  an 
extended  submerged  range  of  action  at  high  speed  is 
desired.  Therefore,  the  space  for  such  equipment  on  the 
underwater  craft  has  to  be  provided  by  increasing  the 
size  of  the  craft.  If  high  surface  speed  is  also  required, 
larger  and  heavier  engines  must  be  installed,  which  ne- 
cessitate an  additional  increase  in  the  size  and  displace- 
ment of  the  vessel.  Maximum  surface  and  submerged 
speeds  cannot  both  be  had  in  one  type  of  submarine,  and 

12 


therefore  a  compromise  which  gives  the  most  efficient 
general  results  has  to  be  effected.  The  main  engines  in 
a  modem  submarine  constitute  approximately  8%  and 
the  storage  batteries  16%  of  the  total  weight  of  the  boat. 
If  greater  surface  speed  is  required,  the  percentage  of 
weight  allotted  to  the  engines  is  increased,  or,  if  greater 
submerged  speed,  the  weight  of  the  batteries  is  increased 
and  smaller  engines  installed.  In  general,  submarines, 
to  be  capable  of  the  highest  possible  speed,  both  for  sur- 
face and  submerged  operations,  must  necessarily  be  of 
the  largest  type,  and  many  predictions  of  giant  subma- 
rines are  made. 

German  cruising  submarines  have  a  maximum  speed 
of  about  17  knots  on  the  surface  and  10  knots  sub- 
merged. 

Details  of  submarine  construction  are  of  less  imme- 
diate importance  than  ways  and  means  to  protect  sur- 
face vessels  from  submarine  attack,  but  details  of  con- 
struction and  of  the  many  life-saving  devices,  such  as  de- 
tachable chambers,  or  conning  towers  and  other  mechan- 
isms which  have  been  proposed,  experimented  with  and 
discarded,  may  be  found  in  the  references  mentioned  on 
a  subsequent  page. 

Equipment. 

The  submarine  when  submerged  so  that  its  periscope  Listening 
does  not  project  above  the  water  is  blind,  but  not  deaf,  i^e^ces 
for  it  is  provided  with  sound  detectors  or  microphones 
that  will  indicate  the  approach  and  direction  of  a  ship, 
if  its  own  machinery  is  at  rest  or  moving  slowly,  with 
noise  so  slight  as  not  to  interfere  with  the  listening. 

The  propagation  of  sound  through  water  is  more 
rapid  and  efficient  than  through  air,  because  water  does 
not  have  so  great  a  cushioning  effect  upon  sound  waves. 
While  we  speak  of  sound  waves,  and  can  measure  their 
amplitude  in  some  cases,  there  is  no  bodily  displacement 
of  the  medium  through  which  they  travel.  In  general 
the  harder,  denser  and  more  incompressible  the  medium, 
the  more  efficient  the  transmission  of  the  sound  waves. 

13 


The  underwater  listening  devices  which  are  so  fre- 
quently availed  of  in  submarines,  and  patrol  boats  and 
destroyers  used  to  attack  them,  consist  primarily  of  a 
large  diaphragm  or  its  equivalent  in  some  other  physical 
form.  The  diaphragm  is  submerged  and  the  pressure 
of  the  water  upon  it  tends  to  cause  it  to  deflect  inwardly 
to  a  slight  extent.  When  the  sound  wave  strikes  the 
diaphragm,  the  deflection  is  increased  and,  when  the 
wave  has  expended  itself,  it  is  followed  by  a  reduction 
of  pressure  which  allows  the  diaphragm  to  recover  until 
the  succeeding  wave  strikes  it. 

The  human  ear  can  detect  sounds  having  periods  of 
vibration  as  low  as  16  per  second  and  as  high  as  30,000 
or  40,000  in  extreme  cases,  so  that  there  is  a  verj'-  wide 
range  of  pitch  over  which  listening  devices  might  be 
used. 

The  vibrations  emitted  from  a  submarine  are  usually 
of  low  frequency,  and  therefore  the  listening  devices 
which  are  particularly  designed  for  submarine  detection 
have  to  be  specially  adapted  to  low  frequency,  at  the  ex- 
pense in  many  cases  of  their  capacity  for  receiving  the 
high  frequency  vibrations;  whereas  with  submarine  sig- 
naling devices,  designed  to  communicate  from  one  vessel 
to  another,  a  frequency  of  several  hundred  vibrations  per 
second  is  found  to  give  better  results. 

In  one  typical  form  of  listening  device  the  diaphragm 
is  provided  with  a  telephone  transmitter.  The  vibrations 
of  the  diaphragm  vary  the  electrical  resistance  in  the 
transmitter,  which  are  either  listened  to  by  a  telephone 
receiver  directly,  or  amplified  by  means  of  relays,  such, 
for  instance,  as  the  audion  and  other  similar  apparatus, 
which  enable  sounds  to  be  heard  which  otherwise  would 
be  inaudible. 

Ways  and  means  to  tune  out  extraneous  noises,  such 
as  the  falling  of  rain  on  the  surface  of  the  water,  the 
noise  of  the  pumps  and  other  machinery  on  the  boat 
carrying  the  listening  device,  and  arrangements  to  de- 
termine the  direction  of  the  source  of  sound  have  been 
given  a  great  deal  of  study  and  been  developed  to  a 
considerable  degree  of  effectiveness.    Sound  waves  tend 

14 


to  emanate  from  the  source  radially,  which  is  availed  of 
in  the  direction-indicating  devices.  However,  the  details 
of  these  devices  are  more  or  less  confidential,  and  only 
the  general  principles  can  be  made  available  to  the  pub- 
He. 

The  superior  gunfire  to  be  expected  from  a  merchant-  Periscope* 
man  which  has  been  properly  equipped  makes  it  prudent 
for  the  hostile  submarine  commander  to  obtain  his  ob- 
servations, for  accurate  aiming  of  the  torpedo,  through 
a  periscope. 

A  submarine  is  usually  equipped  with  two  or  three 
periscopes,  extending  about  twelve  feet  above  the  con- 
ning tower,  the  more  recent  periscopes  being  of  the 
"housing"  type,  which  permits  them  to  be  quickly  raised 
and  then  drawn  down  after  the  observation ;  thus  allow- 
ing the  undersea  boat  to  operate  unseen  much  nearer  the 
surface,  and  not  lose  time  in  changing  its  depth  of  sub- 
mergence. 

It  is  rumored  that  the  latest  German  U-boat  has  a 
short  periscope,  of  from  4  to  6  inches  in  diameter,  ex- 
tending about  8  feet  above  the  periscope  "fair- water," 
which  encloses  the  stufiing-box  through  which  the  peri- 
scope slides  up  and  down.  The  periscope  fair-water 
usually  extends  4  or  5  feet  above  the  top  of  the  conning 
tower.  The  short  periscope  is  used  when  the  boat  is 
moving  at  considerable  speed  through  the  water.  An 
additional  periscope,  which  can  be  extended  to  a  height 
of  from  14  to  16  feet  above  the  periscope  fair- water,  is 
also  provided.  It  is  used  only  when  the  boat  is  station- 
ary or  nearly  so.  This  taller  periscope  is  used  to  reduce 
the  chances  of  exposing  the  conning  tower  and  hull  of 
the  submarine  while  patrolling  in  a  rough  sea,  with  the 
hull  submerged.  It  is  very  small  in  diameter  at  the 
top,  and  is  commonly  called  the  "finger"  periscope. 
Owing  to  the  vibration  prevailing  at  any  speed  above 
four  knots,  it  cannot  be  used  when  a  submarine  is  mov- 
ing rapidly.  A  third  periscope,  smaller  in  diameter,  is 
usually  provided  as  a  spare,  in  case  of  accident  to  the  two 
periscopes  described  above, 

16 


A  periscope  is  usually  designed  to  have  about  a  45* 
angle  of  horizontal  field  of  vision,  and  the  vertical 
field  may  be  less.  It  is  rotated  by  the  observer,  in  order 
to  scan  the  whole  horizon. 

\^Tien  a  submarine  is  cruising  on  the  surface,  the  top 
of  the  periscope  may  extend  to  a  height  of  23  or  24  feet 
above  the  water,  thus  giving  a  range  of  vision  of  about 
six  miles  to  the  horizon,  if  the  day  is  bright;  while  an 
observ^er  standing  upon  the  conning  tower  can  see  the 
horizon  at  a  range  of  only  about  four  and  one-half  miles ; 
however,  the  observer  can  usually  see  much  more  dis- 
tinctly by  his  direct  vision  than  through  the  periscope. 
The  upper  parts  of  ships  can,  of  course,  often  be  seen 
beyond  the  horizon. 

Greatly  increased  optical  efficiency  in  the  periscope 
is  not  a  theoretical  possibility,  although  various  sizes  and 
designs  of  periscopes  have  been  experimented  with.  Any 
increase  of  submerged  diameter,  or  length  of  periscope, 
impedes  the  submerged  speed  of  the  submarine.  The 
older  type  gave  a  great  deal  of  trouble  from  defective 
mechanical  construction;  but  the  more  modem  devices 
are  hermetically  sealed  by  the  manufacturer,  and  are 
reasonably  free  from  condensation  of  moisture  on  the 
lenses  and  from  vibration. 

Experiments  have  been  performed  on  the  subject  of 
decreasing  the  visibility  of  periscopes.  It  is  very  diffi- 
cult to  see  a  periscope,  and  the  artistic  use  of  paint, 
simulating  foam  and  green  water,  is  one  of  the  best 
means  of  making  a  periscope  invisible.  A  periscope  so 
painted,  projecting  a  few  feet  above  the  water  from  a 
motionless  submarine,  can  be  seen  at  a  very  short  range 
only,  and  if  it  is  thrust  up  in  a  quick  observation  and 
then  withdrawn,  the  presence  of  the  submarine  is  usually 
not  disclosed. 

The  use  of  mirrors  has  been  suggested  and  experi- 
mented with,  but  the  conclusion  has  been  reached  that 
their  use  is  not  practicable.  Any  rolling  of  the  subma- 
rine will  change  the  angle  of  incidence  and  reflection,  and 
serve  to  reveal  the  position  of  the  submarine. 

16 


Periscopes  having  their  upper  portions  made  of  glass 
tubing,  to  reduce  visibility,  have  also  been  proposed. 

It  is,  however,  the  wake  of  the  periscope  on  a  moving 
submarine,  rather  than  the  periscope  itself,  that  attracts 
the  attention  of  an  observer. 

A  submarine  may  be  equipped  with  from  one  to  four,  Torpedoes 
or  even  more,  torpedo  tubes.  These  tubes  are  usually 
located  in  the  bow,  but  some  of  the  larger  vessels  also 
have  tubes  in  the  stern,  and  there  are  some  with  broad- 
side tubes.  These,  however,  are  not  German.  The  tubes 
in  the  submarine  usually  being  built  into  the  hull,  it  is 
necessary,  in  order  to  aim  a  torpedo,  to  maneuver  the 
vessel  so  that  the  tube  points  at  the  target.  Swiveled 
torpedo  tubes  are  considered  undesirable  for  submarine 
work. 

A  submarine  carries  as  many  torpedoes  as  possible,  the 
number  varying  with  the  size  and  style  of  the  boat.  ( See 
Torpedoes,  page  31.) 

In  addition  to  being  equipped  with  torpedoes,  some  Mines 
German  submarines  carry  as  many  as  twenty  or  more 
mines.     (See  Mines,  page  33.) 

For  surface  operations,  a  submarine  is  usually  pro-  Guns 
vided,  fore  and  aft,  with  guns  of  from  3  to  6-inch  caliber. 
Sometimes  these  guns  are  secured  rigidly  to  the  deck, 
and  sometimes  housed  within  the  hull  and  thrust  up 
when  they  are  to  be  used.  A  portable  machine  gun  is 
also  usually  provided. 

Telescopic  or  collapsible  masts   are  provided,   and  wirelesa 
wireless  apparatus  operated  upon  them,  particularly  at 
night,  when  the  masts  cannot  be  seen  by  an  enemy  even 
if  he  is  close  at  hand. 

Numerous  devices  and  attachments  have  been  pro-  Net-Cutting 
vided  to  enable  submarines  to  cut  nets,  put  out  divers.  Devices,  etc. 
and  to  send  a  marking  buoy  to  the  surface  in  case  of 
accident,  and  have  proved  more  or  less  ineffective. 

Methods  of  Offense. 

Where  a  surface  fleet  of  naval  vessels  has  control  of  Bases 
the  seas,  it  is  customary  to  have  mother  ships  carry  sup- 

17 


Maneuver- 
ing 


Method  of 
Attack 


plies  and  spare  parts  and  to  accompany  a  fleet  of  sub- 
marines ;  but  unless  the  seas  are  so  controlled  it  is  neces- 
sary to  supply  the  submarines  from  a  shore  base. 

A  base  for  submarines,  to  be  of  any  value,  must  be 
easily  and  safely  accessible,  and  equipped  to  provide  a 
safe  storage  point  for  large  supplies  of  liquid  fuel,  spare 
torpedoes,  food  and  other  requisites  for  their  proper 
maintenance.  Its  location,  if  in  enemy  territory,  must, 
of  course,  be  kept  secret,  as  the  discovery  of  a  submarine 
base  leads  to  the  destruction  or  capture  of  the  subma- 
rines dependent  upon  it.  It  is  reported  that  one  or  more 
German  secret  bases,  along  coasts  under  control  of  the 
Allies,  have  been  discovered  and  destroyed. 

In  areas  that  are  imder  intensive  anti-submarine  rec- 
onnoissance,  both  enemy  and  friendly  submarines  have 
to  remain  submerged  a  large  portion  of  the  time.  If 
they  remain  on  the  surface  during  daylight,  they  are  in 
constant  danger  from  patrol  vessels  and  aeroplanes. 
When  operating  in  the  open  sea,  submarines  may  remain 
on  the  surface  most  of  the  time,  especially  at  night. 

In  maneuvering  it  requires  at  least  60  feet — prefer- 
ably 100  feet — depth  of  water  to  remain  concealed  and 
safe  from  gunfire,  ramming,  or  collision  with  surface 
craft.  Submarines  are  frequently  tested  for  safe  op- 
eration at  depths  of  as  much  as  200  feet,  at  which  depth 
few  effective  obstructions,  trawls,  or  nets  can  be  used 
against  them. 

A  modern  submarine  may,  if  it  is  in  good  order  and 
the  hull  is  not  punctured,  remain  resting  safely  on  the 
bottom  for  a  day  or  more  without  inconvenience  to  the 
crew.  Under  favorable  conditions,  where  the  waters  are 
less  than  200  feet  in  depth,  a  submarine  might  lie  at  rest 
on  the  bottom  and  detect  the  approach  of  a  vessel  several 
miles  away.  In  case  the  water  is  more  than  200  feet  in 
depth,  a  submarine  must  usually  be  kept  in  motion,  to 
obtain  steerage-way,  in  order  to  hold  its  proper  depth  of 
submergence.    This  speed  need  not  exceed  one  knot. 

Submarines,  to  operate  most  effectively,  must  ap- 
proach within  close  range  of  the  vessel  which  is  intended 
to  be  torpedoed ;  but  the  installation  of  offensive  weapons 


18 


on  the  merchant  marine  has  increased  the  necessity  for 
the  utmost  care  being  exercised  by  the  submarine  com- 
mander to  remain  unseen.  It  is  reported  that,  many 
times,  a  submarine  has  followed  a  slow-moving  merchant 
vessel,  at  a  safe  distance,  during  the  daylight  and  has 
remained  undetected,  but,  as  dusk  approached  and  the 
visibility  of  the  submarine  decreased,  the  merchantman 
has  been  overhauled,  when  the  submarine  moved  into  a 
position  to  discharge  one  or  more  torpedoes  at  short 
range,  with  deadly  effect.  Reports  from  abroad  indi- 
cate that  in  many  cases  submarines  have  remained  along 
lanes  of  travel  for  periods  extending  into  weeks,  with  the 
expectation  of  torpedoing  certain  vessels. 

In  its  method  of  attack,  the  submarine  has  many  ad- 
vantages over  its  adversary.  The  ship  to  be  attacked 
presents  a  definite  target,  of  comparatively  large  size, 
and  is  easily  seen  by  the  submarine  conmiander  at  a 
range  where  the  submarine's  periscope  is  usually  quite 
invisible  to  those  on  the  surface  vessel.  Even  though  the 
submarine  be  cruising  on  the  surface  it  is  not  easily  seen, 
because  it  has  a  very  low  freeboard. 

As  the  submarine  approaches  an  enemy's  surface  ves- 
sel it  submerges,  the  periscope  being  the  only  evidence 
of  its  presence.  Periscopic  sighting  of  the  target  is 
necessary,  as  it  has  been  found  impossible  to  see  through 
an  underwater  window  far  enough  for  practical  obser- 
vation. In  the  event  of  accident  to  the  periscope,  a  sub- 
marine must  come  to  the  surface  for  observation  or  else 
maneuver  blindly.  If  the  sea  be  rough,  or  the  weather 
misty  or  foggy,  the  periscope  may  not  be  seen  until  its 
prey  is  destroyed  by  a  torpedo,  and  in  some  cases  not 
even  then.  The  submarine  commander  thus  has  every 
opportunity  to  verify  his  adversary's  identity,  speed  and 
course,  also  to  decide  upon  the  most  vulnerable  point  of 
attack,  and  to  place  his  boat  in  the  best  position  to  dis- 
charge an  effective  shot. 

Torpedoes  may  be  discharged  with  equal  effectiveness 
whether  the  submarine  is  on  the  surface  or  is  submerged, 
but,  at  the  most  effective  range,  say  one-half  mile  or  less, 
the  superior  gunfire  and  greater  accuracy  of  the  guns  of 

19 


armed  merchantmen  and  war  vessels  (because  of  their 
higher  and  steadier  gun  platforms)  make  the  defeat  of 
the  submarine,  operating  on  the  surface,  probable — in 
fact  almost  certain — if  the  torpedo  attack  is  unsuccess- 
ful. A  single  effective  shell  might  disable  or  sink  the 
submarine,  because  of  its  relatively  small  positive  buoy- 
ancy, while  the  surface  vessel  might  have  many  shells 
strike  it  and  still  remain  in  a  seaworthy  condition. 


PROTECTION  OF  VOYAGING  SHIPS  FROM  THE 
SUBMARINE. 

This  subject,  which  is  occupying  the  public  mind  as  is 
no  other,  divides  itself  into  a  number  of  problems,  the 
most  important  being  the  following:  FROM  THE  LIBRARY 

Detecting  the  presence  of  submarines.  OF  * 

Nets,  screens,  guards,  etc.  ^^IIL  ARTHUR  GETi 

Decreasing  the  visibility  of  vessels. 

Speed  of  vessels. 

Special  ship  construction. 

Convoying. 

Detectins^  the  Presoice  of  Submarines. 

Micro-  Many  merchantmen  and  transports  are  equipped  with 

phones  microphones  so  that  they  may  detect  the  presence  of 
submarines,  take  the  necessary  and  available  precautions 
to  defend  themselves,  or  make  escape.  These  instru- 
ments are  of  the  same  general  type  as  those  used  by  the 
submarines  and  have  already  been  described  under 
"Listening  Devices." 

Nets,  Screens,  Guards,  Etc. 

Nets  or  ]\Iany  designs  of  such  devices  are  suggested,  and  most 

le  Attached  ^^  them  are  intended  to  be  attached  to  the  hull  of  the 
to  Vessels     vessel  to  be  protected.    Many  other  suggestions  along 
these  lines,  differing  only  in  some  of  their  minor  char- 
acteristics from  the  foregoing,  have  been  received.    Up 

20 


to  the  present  time  not  one  of  these  proposals  involving 
screens  of  any  kind  has  received  the  approval  of  the 
Navy  Department  or  of  the  Merchant  Marine.  The 
principal  objections  to  these  devices  are  that  they  are 
heavy,  difficult  to  hold  in  position,  mimanageable  in  a 
heavy  sea,  and  that  they  interfere  with  the  speed  and 
with  the  ability  of  the  vessel  to  maneuver.  Many  of 
the  suggested  devices  would  prevent  the  launching  of 
life-boats  or  rafts  from  the  vessel.  It  is  barely  possible, 
however,  that  there  may  be  developed  some  form  of  this 
general  plan  which  will  be  found  practicable.  In  no 
other  field  have  so  many  suggestions  or  so  many  dupli- 
cate inventions  been  presented  to  the  Board. 

Pontoons  and  boats,  from  which  plates  or  screens  are  Pontoons 
sometimes  designed  to  be  suspended,  to  intercept  a  tor-  g^  , 
pedo,  either  self-propelled  or  towed  on  both  sides  of  the  Boats 
vessel  or  convoy  to  be  protected,  have  been  proposed,  but 
require  so  much  power  to  propel  that  they  are  consid- 
ered whoUy  impracticable. 

Many  forms  of  furled  nets  to  be  opened  in  front  of  an  Devices 
approaching  torpedo  have  been  proposed ;  nets  contained  Projected  to 
in  shells  to  be  discharged  from  guns  and  to  be  released  ToScdoes 
on  striking  the  water;  nets  to  be  dropped  over  the  side  of 
a  vessel  when  the  torpedo's  approach  is  noticed,  etc.  The 
operation  of  these  devices,  even  if  practicable  as  mechan- 
isms, would  require  an  appreciable  time  interval,  and 
even  if  the  torpedo's  approach  were  detected,  the  few 
seconds  intervening  between  its  being  observed  and  its 
striking  the  ship  would  probably  be  insufficient  to  per- 
mit of  their  use.    Quick  maneuvering  of  the  ship,  how- 
ever, has  frequently  been  effective  in  dodging  a  torpedo. 

No  effective  means  has  been  found  to  destroy  a  tor-  Torpedo 
pedo  in  flight  or  to  divert  one  from  its  course.  Heavy  Deflectors 
charges  have  been  exploded,  experimentally,  directly  in 
front  of  and  at  the  side  of  torpedoes,  for  the  purpose  of 
determining  the  possibilities  of  deflecting  them  from 
their  course,  but  the  regulating  gyroscope  of  a  torpedo 
immediately  brings  it  back  to  its  normal  course,  so  that 
such  methods  may  be  considered  as  ineffective.  More- 
over, it  should  be  understood  that  there  is  usually  no 

21 


knowledge  that  a  torpedo  is  coming,  until  it  actually  hits 
the  vessel. 

The  deflection  of  a  torpedo  by  water  or  air  jets  oper- 
ated at  the  sides  of  the  vessel  has  been  repeatedly  sug- 
gested, but  the  power  required  to  operate  the  pumps 
necessary  to  furnish  the  streams  of  water,  and  to  give 
adequate  protection  against  a  rapidly  approaching  tor- 
pedo, would  be  much  greater  than  that  required  to  pro- 
pel the  ship.  If  the  power  were  available,  it  might  bet- 
ter be  used  to  drive  the  vessel  at  increased  speed,  by 
means  of  the  propeller. 

Numerous  experiments,  with  devices  employing  mag- 
nets for  arresting  or  deflecting  torpedoes,  have  been 
tried,  w-ith  discouraging  results.  It  has  been  found  that 
magnetic  influences  are  not  felt  at  a  practical  distance. 
(See  "Magnets,  etc.,"  page  8.) 
Mine  Mine-sweeping  boats  and  devices  to  precede  a  vessel 

Sweepers  entering  or  leaving  port  are  sometimes  used  for  the  pur- 
pose of  cutting  the  cables  of  submerged,  anchored  mines, 
sweeping  them  away  or  otherwise  rendering  them  harm- 
less. 

Decreasing  the  Visibility  of  Vessels. 

Smokeless         The  point  of  lookout  on  a  submarine  being  close  to 
Combustion  ^jjg  water,  the  position  of  a  vessel  at  a  distance  can  be 
determined  only  by  observing  its  smoke,  which  floats 
high  in  the  air.    Improved  smokeless  combustion  is  there- 
fore desirable. 

The  visible  particles  in  smoke  can  be  scrubbed  out  with 
several  well-known  types  of  apparatus.  The  whole  sub- 
ject has  been  considered  at  length,  and  the  conclusion 
reached  that  to  handle  the  quantity  of  gases  emitted 
from  a  vessel's  stack,  would  require  such  an  amount  of 
machinery  and  equipment  as  to  make  these  systems  in- 
advisable. The  small  submarine  chasers  are  equipped 
with  internal  combustion  engines  and  emit  no  smoke. 
Torpedo  boats  and  destroyers  use  oil-fuel,  and  can  sup- 
press or  emit  smoke  at  will.  Anthracite  coal  and  other 
smokeless  fuels  have  been  tried  on  coal-burning  vessels, 
with  good  results. 

22 


A  number  of  systems  for  the  smokeless  combustion  of 
soft  coal  have  been  developed,  for  operation  in  power 
plants  and  factories.  Most  of  these  systems  involve  the 
use  of  special  types  of  grates  and  stokers  which  are  not 
often  found  in  the  vessels  at  present  in  service ;  however, 
there  seems  to  be  no  theoretically  insurmountable  ob- 
stacle in  adapting  the  devices  to  marine  work. 

Under  favorable  conditions  of  wind  and  position,  Smoke 
many  vessels  have  saved  themselves  from  torpedo  attack  Screens 
by  the  production  of  a  smoke  screen.  This  may  be 
formed  either  by  incomplete  combustion  of  the  oil  used 
for  fuel  by  most  naval  vessels,  or  it  may  be  created  by 
burning  chemicals,  such  as  phosphorus  and  coal  tar,  or 
mixtures  in  which  both  of  these  and  other  materials  are 
used. 

After  hiding  itself  from  the  submarine  in  a  cloud  of 
dense  smoke,  the  vessel,  if  possessed  of  sufficient  speed, 
may  be  able,  by  a  quick  maneuver,  to  change  her  posi- 
tion and  escape  before  the  submarine  is  able  to  discharge 
an  effective  torpedo. 

In  some  cases,  a  quantity  of  heavy,  black  petroleum.  Blinding 
or  similar  substance,  which  will  float  on  the  surface  of  Peri^opea 
the  water,  has  been  used  to  cloud  the  optical  glass  in 
the  periscope's  exposed  end.  However,  in  view  of  the 
ease  with  which  most  of  these  substances  may  be  washed 
off,  and  the  vast  area  to  be  covered,  the  use  has  been 
abandoned. 

Relative  invisibility  may  also  be  afforded  by  methods  "Camou- 
of  painting.    The  art  of  so-called  "camouflage"  is  ap-  pg^^^g 
plied  to  the  painting  of  ships,  as  well  as  to  land  warfare. 
Ships  are  sometimes  painted  to  resemble  the  sea,  and 
various  devices  have  been  proposed  to  conceal  their  char- 
acter, size  and  identity. 

The  visibility  of  ships  may  be  greatly  reduced  by  de- 
signing them  with  a  low  freeboard,  and  eliminating 
masts,  smoke  stacks,  superstructure,  etc.,  and  this  mat- 
ter has  been  given  a  great  deal  of  study. 

Suggestions  as  to  any  other  method  of  reducing  visi- 
bility will  be  of  interest. 

23 


Speed  of  Vessel. 

The  undeniable  evidence  of  submarine  activity,  which 
has  been  accumulated  during  the  past  few  months,  has 
demonstrated  that  the  immunity  of  a  vessel  to  subma- 
rine attack  is  dependent  very  largely  on  its  speed  and 
also  its  maneuvering  ability.  The  percentage  of  vessels 
having  speeds  of  15  knots  or  more,  and  which  have 
suffered  from  submarine  attack,  is  very  small;  while  the 
loss  of  slow  vessels,  having  speeds  less  than  that  of  a 
submerged  submarine,  is  practically  one  hundred  per 
cent  of  those  attacked. 

The  merchantman  or  other  craft  of  high  speed  quickly 
passes  beyond  the  range  at  which  a  high  percentage  of 
torpedo  hits  can  be  scored,  but  slower  boats  give  the 
submarine  ample  opportunity  to  take  careful  aim  and 
to  score  a  hit  with  almost  every  shot. 

A  ship  steaming  at  twenty  knots  will  cover  a  distance 
of  one-half  mile  in  one  and  one-half  minutes,  but  a  ship 
at  ten  knots  takes  three  minutes;  showing  the  greater 
chance  to  escape  the  high  speed  ships  have  when  the 
submarine  has  finally  maneuvered  into  a  position  for  the 
proper  aiming  of  a  torpedo ;  but,  as  a  submarine  seldom 
has  time  to  get  into  position  to  aim  torpedoes  accurately 
at  a  fast  ship,  such  a  ship  is  almost  immune  to  submarine 
attack,  unless  the  U-boat  happens  to  be  lying  submerged 
in  its  path. 

Merchant  vessels,  in  order  to  be  fast  and  at  the  same 
time  economical  cargo  carriers,  must  of  necessity  be  of 
large  size. 

Special  Ship  Construction. 

The  explosion  of  a  nearby  submarine  mine  or  torpedo 
frequently  tears  great  rents  in  the  ship's  plating,  in 
some  cases  opening  a  jagged  hole  ten  feet  or  more  across. 
The  destructive  effect  at  any  given  distance,  at  the  point 
of  explosion,  depends,  to  a  large  extent,  upon  the  fram- 
ing and  plating,  and  may  be  greatly  diminished  by  spe- 
cial huU  construction. 

24 


Many  suggestions  are  made  for  ships  of  unusual  form  watertight 
to  provide  for  safety  in  case  of  such  explosions ;  most  of  ^""^^"^"^ 
these  plans  being  an  elaboration  of  the  usual  watertight  Air  Cells 
bulkhead  construction,  now  required  in  structural  de- 
sign for  all  modern  ships. 

The  multiplicity  of  watertight  compartments  in  any 
hull  design  tends  to  add  to  the  vessel's  safety.  The  mod- 
ern tank  steamer,  used  to  carry  fluid  cargo,  such  as  pe- 
troleum products  or  molasses,  is  a  good  example  of  this 
design,  which  has  been  in  general  use  for  many  years. 

The  honeycombing  of  hulls  with  air  cells  has  been  pro- 
posed in  an  infinite  number  of  variations,  and  air  tanks, 
such  as  are  now  used  on  liferafts,  have  also  been  sug- 
gested in  various  proposed  arrangements  for  installa- 
tion within  the  hulls  of  vessels. 

The  ordinary  self -baling  lifeboat,  such  as  is  used  by 
the  Coast  Guard  Service,  probably  represents  the  most 
highly  developed  form  of  non-sinkable  ship  that  can  be 
constructed.  Its  hull  is  filled  with  numerous  watertight 
cans  or  boxes,  so  that  injury  will  merely  admit  water  to 
the  space  occupied  by  the  boxes,  and  only  a  little  reduc- 
tion of  the  buoyancy  of  the  boat  will  occur,  as  each  box 
is  an  individual  float.  It  is  very  unusual  for  a  lifeboat 
of  this  type  to  sink,  even  though  the  hull  is  badly 
wrecked. 

The  object  of  a  passenger  vessel  is  to  carry  passen- 
gers, of  a  freighter  to  carry  freight,  and  of  a  war  vessel 
to  carry  offensive  armament.  Air  cells  and  watertight 
compartments  in  their  various  forms  decrease  the  con- 
venience and  carrying  capacity  of  the  different  types  of 
vessels,  and  the  problem  which  has  to  be  solved  for  each 
type  is  one  of  overall  efficiency.  In  other  words,  how 
much  capacity  is  the  designer  justified  in  sacrificing  in 
order  to  increase  the  safety  from  torpedo  attack? 

Cargo-carrying  submarines  of  many  designs,  either  cargo- 
self -propelled  or  towed,  have  been  suggested.    They  are  Carrying 
expensive  to  build  and  operate,  and  are  inefficient.  "  mannes 

Floating  superstructure  and  many  other  special  life-  Life 
saving  devices  have  been  proposed,  but  an  increase  in  the  Saving 
number  of  lifeboats,  rafts  and  regulation  fife  preservers     *^*^*^ 

25 


has  usually  been  considered  preferable,  as  most  of  the 
special  devices  are  inconvenient  and  cumbersome. 

Convoying. 

It  has  long  been  the  custom  to  provide  convoys  for 
merchant  shipping  and  transports  carrjdng  soldiers. 
The  advantage  of  the  convoy  is  very  great,  where  a  num- 
ber of  unarmed  ships  can  be  protected  against  submarine 
attack  by  one  or  two  destroyers,  and  convoys  are  being 
used  wherever  the  need  is  most  important.  In  many 
cases,  however,  the  commanders  of  fast  vessels  prefer 
to  trust  to  their  speed  rather  than  to  allow  themselves 
to  be  hampered  by  the  necessarily  slow  speed  of  a  con- 
voyed fleet. 

OFFENSIVE  AGAINST  SUBMARINES. 
Confining  to  Bases. 

The  question  as  to  why  submarines  are  not  destroyed 
before  they  reach  the  open  sea  is  a  most  natural  one. 
The  best  answer  which  it  is  possible  to  give,  according 
to  the  officers  of  our  Navy  and  those  of  the  foreign 
conmiissions  who  have  visited  this  country,  is  as  follows : 

The  submarine  bases  are  very  strongly  protected  by 
land  batteries,  aeroplane  observers  and  large  areas  of 
thickly  mined  waters,  extending  to  such  distances  that 
the  largest  naval  gun  cannot  get  within  range  of  the 
bases.  Nets,  when  laid,  are  promptly  removed  by  the 
enemy,  whose  trawlers  are  in  turn  attacked  by  our  de- 
stroyers. In  spite  of  these  protections,  there  is  now 
going  on  a  continuous  attempt  on  the  part  of  the  Allied 
navies  to  entrap  or  otherwise  defeat  the  submarines  as 
they  emerge  from  the  protected  areas. 

Means  of  Discovery. 

Nets  There  are  three  general  types  of  anti-submarine  nets : 

the  indicator  net,  the  bomb  net  and  the  entangling  net. 
The  indicator  net  is  solely  for  the  purpose  of  detecting 
the  presence  of  the  submarine.  These  nets  are  generally 
made  of  light  14-inch  stranded  wire  and  have  about  a 
10-foot  mesh,  or  they  may  be  made  of  fiber  rope.  The 
bomb  nets  are  also  of  light  material,  only  sufficiently 

26 


strong  to  carry  the  bombs.  The  entangling  nets  are 
made  of  much  heavier  material,  but  German  submarines 
are  now  equipped  with  various  devices  for  clearing  them- 
selves. 

Anti-submarine  nets  are  so  placed  that  the  upper 
edge  is  between  15  and  20  feet  below  the  surface  of  the 
water.  The  waters  in  which  nets  are  used  are  under  such 
close  surveillance  that  no  submarine  would  operate  on 
the  surface  there  in  the  day  time.  By  keeping  the  top 
of  the  net  under  the  surface,  its  location  is  not  disclosed . 
to  the  enemy. 

The  value  of  nets  with  attached  bombs  is  problemat-  Nets  and 
ical,  owing  to  the  great  danger  from  the  very  rough  han-  ^°"^^s 
dling  which  these  nets  invariably  receive,  especially  when 
attempts  are  made  to  lay  them  in  rough  water.  The 
bombs  and  the  apparatus  which  is  usually  designed  to 
explode  them  are  heavy,  bulky  and  require  occasional 
inspection  for  proper  maintenance. 

An  almost  imperceptible  tidal  current  causes  an 
anchored  net  to  lop  over  to  one  side  so  much  as  to  sink 
the  top  of  the  net  to  a  surprising  extent.  The  behavior 
of  nets,  either  towed  or  anchored  in  a  current,  is  very 
difficult  to  comprehend,  until  seen. 

The  dragging  of  trawls,  or  nets,  by  trawlers  and  de-  Trawling 
stroyers,  not  only  with  the  view  of  locating  submerged 
submarines  but  also  to  sweep  up  mines,  is  frequently 
suggested.  Under  certain  conditions  this  operation  is 
practicable  and  effective,  and  has  been  constantly  em- 
ployed abroad  since  the  beginning  of  the  war. 

Aeroplanes,  dirigible  balloons,  kites  and  aircraft  of  Aircraft 
all  sorts  are  used  for  detecting  the  presence  of  subma- 
rines. They  may  be  operated  either  from  shore  or  from 
the  larger  ships,  and  are  sometimes  very  effective;  as, 
under  favorable  conditions,  a  submarine  is  discernible 
from  aircraft  flying  at  a  proper  height,  even  though 
the  submarine  be  submerged  to  a  considerable  depth. 

While  aeroplanes  have  been  thus  used  successfully  in 
the  English  Channel,  they  are  unable  to  operate  far  out 
at  sea,  where  the  submarines  are  now  most  active.  The 
construction  of  mother  ships  for  carrying  and  launching 

27 


Optical 
Detection 


Wake  of 
Submarine 
or  Torpedo 


Seeing 

Under 
Water 


aeroplanes  is  necessarily  a  slow  process  under  present 
conditions,  when  all  shipyards  are  overloaded  with 
other  important  work. 

Many  devices  which  depend  upon  optical  means  of 
detection,  such  as  special  forms  of  telescopes  and  field- 
glasses,  to  be  mounted  on  ships  or  on  scouting  vessels, 
are  suggested.  Experienced  and  alert  lookouts,  how- 
ever, have  proved  to  be  the  most  essential  factor.  With- 
out such  men,  no  optical  device  appears  to  be  of  value, 
and  at  night,  or  in  bad  weather,  such  devices  are  apt  to 
be  unreliable. 

The  fact  that  a  moving  torpedo  leaves  in  its  wake  a 
stream  of  air-bubbles  caused  by  the  exhaust-air  from  its 
propelling  engines,  offers  under  favorable  conditions, 
one  means  for  discovering  its  approach.  This  evidence 
is,  however,  difficult  to  detect  in  a  rough  sea  or  at  night, 
and,  furthermore,  the  bubbles  do  not  reach  the  surface 
of  the  water  until  after  the  torpedo  has  travelled  onward 
a  distance  of  from  50  to  200  feet  towards  its  target. 
Only  a  very  small  percentage  of  torpedoes  are  seen. 

Many  proposals  for  boats  with  glass  windows  in  the 
bottom,  and  other  means  for  observing  submerged  ob- 
jects have  been  made.  The  waters  in  which  submarine 
activity  is  most  pronounced  are  so  lacking  in  transpar- 
ency that  experiments  have  proved  it  impossible  to  see 
objects  such  as  submarines  at  an  average  distance  of 
more  than  10  or  15  feet.  Even  in  the  clearest  sea  water, 
objects  under  the  surface  cannot  be  seen  if  distant  more 
than  100  or  150  feet. 

Many  special  forms  of  searchlights  and  projectors,  to 
enable  an  observer  to  see  a  greater  distance  through 
water  have  been  suggested  and  experimented  with,  but 
so  far  none  of  these  devices  has  proved  successful. 

It  will  be  seen  that  each  of  the  above  methods,  however 
useful,  has  its  limitations;  therefore,  scientists  and  in- 
ventors should  apply  themselves  not  only  to  the  task  of 
improving  these,  but  also  of  finding  supplementary 
methods  and  devices. 


28 


Patrol  for  Submarines. 

In  open  waters,  where  storms  and  heavy  seas  are 
encountered,  the  patrol  for  submarines  is  generally  car- 
ried on  by  large,  fast  boats  of  the  destroyer  type.  In 
the  more  protected  waters  the  patrol  for  submarines  de- 
volves upon  light,  fast  surface  craft,  aircraft  and  sub- 
marines. 

Submarines  Used  Against  Submarines. 

Submarines  have  very  low  visibility.  They  were  pri- 
marily designed  to  operate  against  the  large  surface  ves- 
sels, and  it  has  been  the  general  impression  that  subma- 
rines are  not  effective  against  submarines.  This  belief 
was  also  held  by  the  general  naval  staffs  of  the  various 
combatants  at  the  beginning  of  the  war;  however.  Allied 
submarines  have  been  successfully  used  in  destroying 
enemy  submarines. 

In  operating  against  hostile  submarines,  the  hunting 
submarine  may  employ  one  of  two  methods;  it  may  re- 
main totally  submerged  and  take  observations  by  thrust- 
ing up  the  periscope  every  few  minutes,  or  it  may  remain 
on  the  surface  and  only  dive  when  the  enemy  submarine 
is  sighted.  In  both  cases  the  hunting  submarine  maneu- 
vers very  slowly,  in  order  to  avoid  attracting  the  atten- 
tion of  the  enemy,  and  to  prevent  detection  by  means  of 
listening  devices.  The  method  of  total  submergence  is 
used  in  restricted  waters,  such  as  channels  and  lanes 
through  which  the  enemy  submarine  must  pass.  Torpe- 
does are  used  when  submarines  fight  each  other,  and,  if 
possible,  the  extremely  effective  ram.  All  submarines 
can  ram  without  specially  designed  devices  for  so  doing. 

Destruction  of  Submarines. 

A  submarine  is  most  vulnerable  to  attack  from  gun- 
fire when  it  is  on  the  surface,  recharging  the  storage  bat- 
teries; for  the  gases  rising  during  this  operation  are 
stifling  and  must  be  vented  into  the  air,  and  several  min- 
utes are  required  to  close  the  hatches  and  submerge. 

Quick  firing  guns  of  sufficient  caliber  and  depth 
charges  are  used  by  surface  vessels,  such  as  destroyers 

29 


Gunfire 


Bombing 

Hydro- 

Aeroi»lanes 


and  chasers,  when  they  are  unable  to  discharge  an  effec- 
tive torpedo. 

A  rapid-fire  gun  is  effective  when  the  submarine  is 
within  close  range  of  the  gun;  but  when  only  the  con- 
ning tower  is  exposed  the  target  is  so  small  that  it  is 
difficult  to  hit. 

A  submerged  submarine  can  be  reached  with  ordi- 
nary service  shells  only  by  high  angle  fire,  because  at  low 
angles  they  ricochet  on  the  surface  of  the  water. 

The  Navy  has  one  or  more  types  of  shell  that  pene- 
trate the  water  satisfactorily,  and  any  improvement 
would  be  along  the  line  of  straighter  underwater  tra- 
jectory and  reduced  underwater  resistance.  The  screw- 
nosed  shell  has  been  suggested  many  times,  but  it  would 
seem  that  inventors  are  laboring  under  a  misapprehen- 
sion: viz.,  that  the  shell  will  screw  its  way  into  the  water, 
whereas  a  shell  rotates  only  once  in  about  25  or  30  cali- 
bers, and  the  fraction  of  a  revolution  which  it  makes 
while  entering  the  water  is  negligible. 

The  powerful  effect  of  any  submarine  explosion  on  all 
neighboring  bodies  provides  a  simple  means  of  destroy- 
ing or  crippling  an  undersea  boat.  Once  it  has  been 
even  approximately  located,  the  setting-off  of  a  heavy 
charge  of  high  explosive,  well  submerged  within  about 
50  feet  of  the  submarine,  will  bring  about  this  result. 

Howitzers  and  mortars  to  throw  depth  charges  at  a 
submarine  have  been  proposed,  but  the  deck  of  a  mer- 
chant vessel  would  have  to  be  reinforced  to  support  the 
recoil,  if  heavy  charges  were  to  be  handled.  Catapults 
have  been  proposed  as  a  substitute  for  howitzers,  but  are 
believed  to  be  theoretically  and  practically  less  efficient 
for  this  work. 

The  rapid  development  and  improvement  of  the  depth 
bomb,  and  the  increased  carrying  capacity  of  the  mod- 
ern high-powered  hydro-aeroplane,  have  made  possible 
a  new  type  of  "bombing  hydro-aeroplane,"  designed  to 
carry  a  considerable  number  of  bombs,  each  containing 
a  heavy  charge  of  high  explosive. 


30 


A  great  many  nest  arrangements  of  torpedoes  have  Nests  of 
been  suggested  and  considered,  also  torpedoes  combined  Torpedoes 
with  nets,  but  the  authorities  do  not  believe  that  any 
of  these  combinations  are  as  practicable  as  other  means 
now  at  hand. 

The  idea  of  having  chasers  towing  mines  has  often  Towine 
been  suggested  and  used  to  some  extent.    This  is  a  good  M"*®^ 
method  when  the  whereabouts  of  the  submarine  are 
known. 

Torpedoes  to  be  controlled  by  sound  have  been  fre-  Torpedo 
quently  proposed,  the  torpedo  to  be  tuned  to  automat-  By^sour^ 
ically  steer  itself  and  strike  the  vessel  destined  to  be 
destroyed.    This  design  has  been  very  carefully  consid- 
ered by  torpedo  experts  and  associated  scientists. 

To  develop  such  a  weapon  would  require  years  of 
experimentation  and  while  a  successful  design  might  be 
attained,  the  relative  increase  in  value  would  hardly 
compensate  for  the  time  and  study  necessary. 

There  are  many  methods  for  dealing  with  the  sub- 
marine when  its  whereabouts  are  determined.  The  prob- 
lem lies  rather  in  locating  the  submarine. 

TORPEDOES. 

The  modem  submarine  torpedo  varies  in  size  accord-  size 
ing  to  the  service  for  which  it  is  intended,  and  ranges 
from  14  inches  in  diameter  and  15  feet  in  length  to  21 
inches  in  diameter  and  21  feet  in  length,  weighing  from 
1,000  to  2,600  pounds,  the  smaller  type  being  used  by 
the  Germans  to  sink  unprotected  freight  and  passenger 
ships  at  short  range. 

It  is  capable  of  a  speed  of  more  than  30  miles  per  Speed 
hour,  and  when  traveling  at  normal  speed,  possesses 
great  momentum,  about  65,000  foot  second  pounds. 

A  torpedo  is  projected  by  means  of  a  special  form  of  Method  of 
tube  or  gun.    The  tube  is  usually  built  into  the  hull  of  discharge 
the  submarine,  in  which  case  it  is  aimed  by  maneuvering 
the  boat.    In  the  case  of  destroyers  and  battleships,  the 
torpedo  may  be  projected  from  submerged  tubes  or  from 
deck  tubes. 

31 


Generally  speaking,  torpedoes  are  projected  from 
submerged  tubes  by  compressed  air  and  from  deck 
tubes  by  a  small  charge  of  gun  powder.  Submerged 
tubes  on  battleships,  however,  may  be  designed  to  use 
either  powder  or  compressed  air.  When  the  torpedo 
is  fired  from  a  submerged  tube,  the  compressed  air  or 
the  gas  from  the  powder  follows  the  torpedo  out  of  the 
tube  with  a  rush,  and  causes  an  eruption  on  the  surface 
of  the  sea,  which  is  visible  for  a  considerable  distance. 
As  a  result  of  the  warning  given  by  this  eruption,  ves- 
sels have  sometimes  been  able  to  escape  the  torpedoes 
by  a  quick  maneuver. 

The  modem  torpedo  is  self-propelled,  being  driven 
through  the  water  by  its  own  compressed  air  motor,  the 
air  being  supplied  from  a  strongly  built  reservoir  within 
the  body  of  the  torpedo  itself.  Torpedoes  directly  op- 
erated by  internal  combustion  engines  as  motive  power 
have  been  experimented  with  and  discarded. 

The  range  of  a  torpedo  is  approximately  a  mile,  those 
designed  for  use  on  battleships  and  destroyers  being 
longer  ranged  than  those  for  use  on  submarines.  The 
great  difficulty  in  getting  proper  direction  and  suffi- 
cient motive  power  to  give  the  required  speed  for  a  long 
duration  of  time  renders  the  long  range  torpedo  imprac- 
ticable. It  is  stated  that  the  latest  German  torpedo  has 
a  range  of  about  2,000  yards,  as  the  compressed  air 
storage  reservoir  has  been  reduced  in  size  in  order  to 
increase  the  charge  of  high  explosive  in  the  warhead. 
The  charge  is  said  to  be  from  300  to  400  pounds. 

The  torpedo  keeps  a  fairly  accurate  course  by  means 
of  a  gyroscopic  steering  mechanism,  which  is  immune  to 
outside  magnetic  disturbance. 

The  depth  at  which  a  torpedo  travels  may  be  regu- 
lated to  hit  the  most  vital  part  of  the  vessel,  and  that  is 
usually  about  10  feet  below  the  surface.  In  case  of 
torpedo  attack  against  an  armored  ship,  the  torpedo, 
to  be  dangerous,  should  strike  beneath  the  armor  belt, 
which  usually  extends  about  10  feet  below  the  water  line. 

32 


Torpedoes  are  usually  provided  with  means  to  cut,  Net-Cutting 
more  or  less  effectively,  through  nets  placed  in  their  devices 
paths. 

The  detonation  of  the  torpedo  is  accomplished  through  Detonation 
a  mechanism  placed  within  its  warhead;  and  if  the  tor- 
pedo is  checked  in  its  forward  motion,  the  firing  mechan- 
ism instantly  ignites  the  heavy  charge  of  explosive  con- 
tained within  the  warhead.  It  is  not  necessary  to  strike  a 
firing  pin  on  the  end  of  a  torpedo  to  detonate  the  charge. 

Many  suggestions  have  been  submitted  to  the  Board  Controlled 
for  a  torpedo  to  be  electrically  propelled  from  a  ship  by  prom^swp 
means  of  a  flexible  cable  connecting  it  with  the  ship. 
This  was  the  first  type  of  torpedo  built,  but  was  dis- 
carded for  the  present  dirigible  type,  as  the  weight  of 
cable,  difficulties  in  insulation,  etc.,  render  it  of  no 
practical  value. 

MINES. 

Generally  speaking,  there  are  two  types  of  mines:  stationary 
fixed  and  floating.  The  fixed  or  stationary  submarine  M"*«s 
mine  is  fired  by  contact,  electricity,  timing  device  or 
fuse.  Such  mines,  which  are  extensively  used  by  all  na- 
vies, are  rugged  in  design  and  may  contain  large  charges 
of  explosives.  They  are  placed  in  position  by  subma- 
rines and  other  especially  equipped  mine-laying  vessels. 
Such  a  mine  is  provided  with  an  anchoring  device  and 
is  deposited,  if  possible,  in  harbors  and  channels  of  the 
enemy  or  in  the  paths  of  ocean  travel. 

Floating  mines  differ  from  fixed  mines  in  that  they  Floating 
are  unanchored,  and  imless  guard  boats  are  at  hand  to  Mines 
warn  friendly  vessels  of  their  proximity,  may  be  as  dan- 
gerous to  friend  as  to  foe.    Such  mines  must  be,  accord- 
ing to  laws  of  war,  designed  to  become  inoperative  with- 
in a  few  hours  after  being  set  adrift. 

The  German  floating  mines  are  often  cast  adrift  in 
pairs,  connected  by  a  line  about  100  feet  long.  If  a 
ship  runs  between  the  two  mines  they  are  drawn  along- 
side the  ship,  and  exploded. 

Many  proposals  have  been  received  suggesting  the  use  Contact 
of  a  contact  depth  mine,  which  will  rise  to  the  surface  if  R^^* 

33 


failing  to  contact.  This  type,  however,  is  considered  un- 
necessary and  inadvisable.  The  essence  of  the  depth 
charge  is  that  it  explodes  in  the  vicinity  of  the  subma- 
rine, in  case  it  fails  to  strike  the  boat  itself.  The  use  of 
the  contact  depth  mine  presupposes  the  necessary  ac- 
curacy to  strike  the  target.  The  recovery  feature  is  of 
no  particular  value,  and  would  necessitate  numerous 
safety  precautions  to  insure  absolute  safety  in  picking 
up. 


REFERENCES  ON  THE  SUBMARINE  AND  KINDRED 

PROBLEMS. 

The  student  is  advised  to  consult  the  following  publi- 
cations, which  may  be  found  in  any  public  library : 

The  General  Electric  Review,  Schenectady,  N.  Y., 
August,  1917,  containing  "Bibliography  of  the  Litera- 
ture of  Submarines,  Mines  and  Torpedoes,"  by  David 
B.  Rushmore,  which  gives  a  list  of  books  and  papers  in 
relation  to  the  subject. 

The  Journal  of  the  Franklin  Institute,  Philadelphia, 
Pa.,  August,  1917,  in  which  appears  an  article  entitled 
"The  Submarine  in  Periodical  Literature,  from  1911  t» 
1917,"  which  gives  a  digest  of  a  number  of  articles  oa 
the  subject,  and  is  helpful  for  anyone  who  wishes  to  get 
a  general  idea  of  the  problem. 

Scientific  American  issues  of  1917  and  1918,  "Sub- 
marine Problem." 


34 


FROM  THE  LIBRARY 

OF  A 

mi  ARTHUR  GETZ 


List  of  References  on 

SUBMARINE  STRATEGY  AND  TACTICS 

Prepared  by  Library  Service  Bureau,  United  Engineering  Society, 

29  West  39th  St.,  New  York  City,  September  14, 

1917,   for   the   Naval   Consulting   Board. 

1912 — Nimitz,  Lieut.  C.  W. 

Military  value  and  tactics  of  modern  submarines. 
Proc.  U.  S.  Naval  Inst.,  1912,  Dec,  vol.  XXXVIII,  pp. 
1193-1211. 

Discusses  the  factors  of  communication,  mobility,  invul- 
nerability and  o£fensive  strength,  the  relative  advantages 
and  disadvantages  of  submarines  and  submersibles. — Coast 
defence  submarines. — Tactics  of  an  offensive  sea-keeping 
group  of  submarines. 

1914— Biles,  J.  H. 

The  protection  of  battleships  against  submarine  attack. 
Engr.,  1914,  July  10,  vol.  118,  pp.  33-35. 
The  defensive  aspect  of  submarine  tactics  is  referred  to, 
with  particular  reference  to  the  advisability  of  providing 
battleships  with  bottom  armour.  The  points  for  discussion 
were  as  follows:  (1)  Is  4-inch  armor  sufficient  protection 
against  torpedoes  to  justify  its  adoption  in  battleships  of 
the  class  of  the  later  Dreadnoughts.''  (2)  Is  the  submarine 
menace  of  sufficient  importance  to  justify  the  adoption  of 
4-in.  armor  protection  on  the  bottom.''  (3)  Is  the  sub- 
marine menace  of  sufficient  importance  to  justify  the 
building  of  smaller,  slower  battleships  of,  say,  16000  tons 
displacement  of  18  knots?  (4)  Is  the  method  of  apply- 
ing armor  to  the  bottom  of  sufficient  value  in  itself  to 
justify  the  adoption  of  a  form  of  ship  which  offers  greater 
resistance  than  the  ordinary  form? 

!•§  16— Robinson,  R.  H.  M. 

The  modern  submarine  in  naval  warfare. 
J.  Franklin  Inst.,    1915,  vol.  179,  pp.  283-311. 
Extremely  valuable  paper.     The  two  general  roles  of  sub- 
marines, viz.  the  defensive  and  offensive  roles,  are  dis- 

35 


cussed  at  length.  The  question  of  the  tactical  use  of  the 
submarine  in  groups  is  also  commented  upon.  For  the 
purpose  of  tactics,  submarines  are  considered  in  this 
article,  according  to  their  capabilities,  under  three  heads, 
viz.,  harbor  defense,  coast  defense  and  sea-keeping  oflFensive 
submarines. 

1916— Horsnail,  W.  O. 

Submarines  versus  surface  craft  for  future  navies. 
Fortnightly  Rev.,  1915,  Oct. 

The  question  is  being  asked  whether  the  functions  of  a 
modern  navy   can  be   carried   out   by   submarine   craft. 

These  functions  are: 
"(1)   To  fight  enemy  ships. 

(2)  To  blockade  an  enemy's  coasts. 

(3)  To  capture  enemy  merchant  vessels  in  all  parts  of 
the  world. 

(4)  To  chase  and  destroy  enemy  commerce-raiders. 
(6)   To  destroy  forts  on  shore. 

(6)  To  assist  land  forces  by  shelling  an  enemy's  posi- 
tion within  range  of  the  sea. 

(7)  To  obtain  information  regarding  an  enemy's  naval 
movements. 

(8)  To  protect  the  transport  of  troops  and  supplies." 
These  functions  might  be  modified  if,  for  instance,  com- 
merce might  be  carried  by  submarine  vessels  or  by  air- 
craft. But  a  consideration  of  this  question  shows  that 
this  will  be  impossible  or  impracticable.  Merchant  types 
will  remain  the  same.  The  other  functions  may  be  con- 
sidered as  conducted  against  submarine  naval  types. 

(The  author  concludes  that  it  is  possible  to  develop  sub- 
marine naval  types  corresponding  to  the  present  elements 
of  naval  construction — battleships,  battle  cruisers,  destroy- 
ers, etc.  High  surface  speed  for  submarine  or  submersi- 
ble type  is  contingent  upon  the  development  of  an  "oil 
turbine."  Other  types,  carrying  armor  and  heavy  guns, 
are  practicable  from  the  standpoint  of  design,  and  they 
could  perform  their  functions.) 

36 


Resisting  submarine  attack. 
United  Service  Gazette. 
Canadian  Military  Gazette,  1915,  June  22. 
The  submarine  has  had  more  success  amongst  large  battle- 
ships in  the  present  war  than  most  experts  anticipated. 
Some,  indeed,  believe  with  Vice-Admiral  Sir  Percy  Scott, 
that  the  submarine  was  destined  to  drive  the  battleship 
from  the  sea,  but  the  majority  held  the  other  view.  Up  to 
the  present  no  Dreadnought  has  been  sent  to  the  bottom  by 
this  agency,  so  far  as  oflScially  known.  In  this  connection 
the  distinction  between  the  Dreadnought  and  the  pre- 
Dreadnought  is  important.  In  the  Dreadnought  type  the 
bottom  has  been  more  effectively  divided  than  in  the  previ- 
ous construction,  and  this  double  bottom  and  division  sys- 
tem has  been  extended  with  each  successive  ship;  and 
though  a  full  test  has  probably  not  been  made,  the  pro- 
tection is  undoubtedly  very  complete.  Notwithstanding 
this,  the  case  of  the  "Lusitania"  was  disquieting,  for  the 
underwater  construction  of  the  ship  was  to  an  extent  that 
of  the  latest  Dreadnoughts.  In  both  the  "Lusitania"  and 
the  "Titanic"  the  watertight  doors  were  closed;  and  since 
apparently  none  of  the  present  Dreadnoughts  have  en- 
countered the  latest  type  of  torpedo  from  a  submarine,  and 
none  have  been  subjected  to  the  experience  of  the 
"Titanic"  with  an  iceberg,  the  effect  of  any  of  these  con- 
ditions on  the  latest  ship  construction  of  the  navy  is  still 
a  matter  of  speculation. 

There  are  two  ways  of  affording  complete  protection  to 
the  bottoms  of  the  vessels  from  submarine  attacks — either 
to  build  boats  that  will  destroy  the  submarine,  or  cover  the 
bottom  of  the  ship  with  armor  protection  suflScient  to  resist 
the  torpedo.  The  latter  method  has  long  been  under  dis- 
cussion. It  is  estimated  that  covering  the  bottom  with  a 
sufficient  thickness  of  armor  would  reduce  the  speed  of  the 
ship  by  at  least  two  knots  under  forced  draft.  Of  course, 
the  adoption  of  such  protection  by  all  navies  would  re- 
duce the  speed  all  around,  with  no  resulting  comparative 
loss. 

In  order  to  fit  the  armor,  the  design  of  bottoms  would 
have  to  be  different  from  the  present  form,  and  experts 

37 


claim  that  the  change  •£  construction  would  result  in  a 
design  for  a  ship  smaller  and  shorter  than  at  present. 
This  would  return  the  size  of  battleships  to  more  moderate 
dimensions.  These  changes  would  necessitate  lighter  armor 
on  other  parts  of  the  hull,  a  certain  sacrifice  of  gun-power, 
and  other  compromises. 

191$ — Degouy,  Admiral. 

The  protection  of  commercial  steamers. 
Revue  des  Deux  Mondes,  1916,  Dec.  15. 
Submersibles  and  submarines  have  tremendously  increased 
in  size,  speed,  radius  of  action,  and  armament.  There  is 
talk  of  a  submersible  cruiser  of  5,000  tons,  and  it  seems 
that  some  submarines  are  carrying  150  mm.  guns  in  addi- 
tion to  their  torpedoes.  The  large  new  types  make  18  or 
20  knots  on  the  surface  and  12  to  14  submerged.  They 
have  petroleum  engines,  or  motors,  whose  fuel  they  can 
replace  from  any  victim's  store  or  cargo.  They  have  most 
elaborate  wireless  equipment.  German  submarines  have 
bases  in  many  quite  well-known  localities,  threatening  all 
trade  routes.  Despite  the  vigilance  of  the  United  States 
authorities,  they  are  probably  in  wireless  communication 
with  agents  in  that  country,  and  receive  information  as 
to  sailings,  cargoes,  descriptions,  etc.,  of  outgoing  vessels. 
They  doubtless  do  not  too  closely  conform  to  the  rules 
concerning  territorial  waters  in  watching  for  their  prey. 

How  can  ships  be  protected.'  Can  they  protect  them- 
selves.'' Can  convoys  be  provided?  What  are  the  best 
methods  to  protect  them? 

The  problem  presents  itself  under  two  aspects.  Pro- 
tection is  needed  throughout  the  voyage  in  the  smaller 
bodies  of  water.  In  the  Atlantic,  protection  is  particularly 
needed  in  getting  out  into  the  high  sea,  and  in  making 
land.  The  submersible  high-seas  cruiser  has  happily  not 
yet  appeared ;  but  who  can  say  that  it  may  not  be  in 
process  of  construction?  As  to  self -protection,  the  guns 
so  far  in  general  use  are  smaller  than  those  that  seem 
to  be  borne  by  the  new  type  of  submersibles,  which  are 
apparently  budding  into  bombarding  war  vessels.  For  the 
liners^  many  gunS;  gunners,  and  skilled  observers  would 

38 


be  needed,  as  well  as  captains  bold  enough  to  fire  upon 
the  pirates,  although  superiors  recently  condemned  to 
death  one  who  did  fire. 

For  the  shorter  and  more  dangerous  lines  of  travel,  for 
example  in  the  Mediterranean  and  the  North  Sea,  it  might 
help  to  follow  unusual  and  varying  courses,  but  the  ves- 
sels should  be  convoyed  out  and  in.  For  this  duty,  fast- 
sailing,  small  craft  are  best;  we  can  not  have  too  many. 

Furthermore,  the  voyages  should  be  shortened  as  much 
as  possible.  Why  not  make  more  use  of  mixed  transporta- 
tion ?  Many  voyages  could  be  shortened  by  utilizing  shore 
transportation.  In  many  places  by  utilizing  railroads  and 
motor  vehicles,  the  danger  could  be  reduced  60  per  cent. 

In  the  Atlantic,  vessels  should  be  well  covered  in  getting 
away  frdm  land,  and  in  making  land.  To  do  this  effective- 
ly, careful  and  thorough  organization  would  be  necessary. 
Trying  to  ferret  out  submarines,  especially  when  our 
cruisers  must  respect  territorial  waters  while  the  sub- 
marines can  disregard  their  limits  and  escape  detection, 
is  an  almost  hopeless  task. 

Here,  too,  convoys  for  the  entire  voyage  would  be  best; 
but  we  always  come  into  contact  with  "established  princi- 
ples." We  can  not  get  enough  small  craft,  and  we  hear 
such  objections  as  that  of  the  retardation  of  fast-sailing 
liners  by  slower  convoys.  Better  more  time  and  greater 
safety.  Besides,  every  sailor  knows  that  the  liner  could 
tow  her  convoy,  and  she  would  not  need  to  throw  out  a 
steel  cable  to  do  it.  The  smaller  vessel  could  follow  in 
her  wake. 

There  are  many  minor  means  of  lessening  the  danger 
to  vessels.  Are  the  least  visible  colors  used  for  painting? 
Can  the  art  of  "making-up"  be  utilized?  What  can  be 
done  by  means  of  false  water  lines,  false  lengths  for  the 
ship,  false  heights  for  masts,  smoke-stacks,  etc  ?  AH  these 
Retails  would  have  to  be  put  into  practice  outside  the  port 
of  departure.  They  could  be  done  after  sailing;  one  could 
put  into  certain  convenient  places  for  the  purpose  when 
the  seas  ran  too  high.  The  use  of  paint  and  other  artifices 
like  those  mentioned  would  assist  in  misleading  the  enemy 
in  his  calculations  of  distance,  etc. 

39 


Munitions  should  not  be  carried  on  personnel  transports. 
There  are  enough  explosives  aboard  for  the  guns  carried 
as  an  armament  in  these  cases.  These,  too,  should  not  be 
considerable,  and  they  should  not  be  placed  in  the  hold, 
where  a  mine  or  a  torpedo  may  explode  them.  Better  an 
explosion  on  deck  than  in  the  hold.  Protective  or  palliative 
measures  could  be  provided  on  deck,  though  the  probable 
inconveniences  are  recognized  as  serious. 

Wireless  telegraphy,  collective  and  individual  life-sav- 
ing equipment,  numerous  carefully  constructed  ship's  boats, 
perfected  methods  for  promptly  lowering  the  boats,  not- 
withstanding any  possible  inclination  a  torpedoed  ship 
might  take — all  these  should  receive  our  most  careful  at- 
tention. Means  should  be  worked  out  for  eliminating  the 
smoke,  which  reveals  at  great  distances  the  presence  of  a 
vessel. 

In  default  of  the  means  of  providing  convoys  for  the 
entire  voyage,  there  should  be  organized  a  route  of  relay 
protection,  over  which  a  ship  could  pass  from  one  protected 
zone,  or  from  one  safety  lane  to  another.  It  will  be 
noted  that  there  is  a  striking  resemblance  between  the 
methods  that  it  would  be  well  to  adopt  in  the  maritime 
theaters  of  operations  and  those  already  established  on 
land  in  a  warfare  of  movement.  There  are  not  two  ways 
of  waging  war ;  there  is  only  one,  the  proper  way. 

There  is  no  intention  here  to  open  a  discussion  which 
will  doubtless  be  brought  up  later.  But  it  may  be  repeated 
that  we  shall  not  succeed  in  wresting  from  the  Germans 
the  undeniable  mastery  which  they  exercise,  not  on  but 
under  the  sea,  except  by  attacking  methodically  and  suc- 
cessively, with  all  the  appropriate  means  of  action,  the 
naval  bases  of  their  submarines,  for  the  purpose  of 
destroying  them  or  hermetically  sealing  them  up. 

1917 — Defense  against  submarines  by  smoke  screens. 
Army  &  Navy  Jour.,  1917,  March  10. 
The  device  used  on  British  merchant  steamers  to  envelop 
themselves  in  smoke  includes  two  drums  that  are  attached 
to  the  after  deck,  one  on  each  side  of  the  ship.    Each  drum 
is  filled  with  phosphorus.     When  the  lookout  sights  an 

40 


undersea  faoat^  an  order  is  gives  to  fire  the  phosphorus  in 
the  drums,  from  which  ahnoet  immediatelj  hearj  clouds  of 
Mack  smoke  pour,  entirely  enveloping  the  ship,  and  leav- 
ing such  a  long  trail  that  the  submarine  cannot  locate  the 
fleeing  merchantman. 

McGrath,  Senator  P.  T. 

The  strategic  value  of  Newfoundland  in  a  submarine  war. 
Forum,  1917,  Apr,,  vol.  57,  no.  4,  pp.  431-36. 
It  is  claimed  that  the  possession  of  this  island  is  indis- 
pensable to  the  future  security  of  the  United  States  in  the 
event  of  war.  The  chief  value  of  Newfoundland  lies  in 
the  fact  that  the  power  which  possesses  it  has  in  it  the 
means  of  providing  a  base  for  its  naval  forces  rarely 
equaled  elsewhere  in  the  world,  and  of  exercising  thereby 
an  influence  on  Canada's  development  which  cannot  be 
otherwise  approached.  It  must  be  perfectly  obvious,  there- 
fore, as  an  outcome  of  the  lessons  of  naval  warfare  in  the 
present  struggle,  that  on  the  one  Yland  the  power  owning 
Newfoundland  and  controlling  operations  within  its  waters, 
would  be  able,  by  use  of  nets  and  other  appliances  em- 
ployed to  impede  submarines  at  present,  to  render  Belle 
Isle  Strait  inaccessible  for  these,  while  the  type  of  big 
guns  now  in  use  would  enable  land  forts  to  prevent  hostile 
cruisers  forcing  through  that  channel;  whereas,  on  the 
other  hand,  submarine  operating  by  the  power  owning 
all  the  adjacent  seaboard,  would  render  it  impossible  £o» 
an  enemy  to  approach  this  seaway  at  all. 

1917 — Degouy,  Admiral. 

The  submarine  war  of  1917. 

Revue  des  Deux  Mondes,  1917,  Jan.  15. 

From  the  beginning  the  necessity  has  been  recognized  of 

breaking  up  the  enemy's  organizations  of  small  bases  for 

submarine  supplies,  fixed  as  well   as  mobile.      There  is 

at  present  much  trouble,  in  this  respect,  connected  with 

the  coasts  of  Spain,  where   various   activities   are  being 

carried  on. 

But  I  repeat  that  the  difficulty  of  operating  agamst  the 
large  submersibles,  with  their  vastly  increased  radius  of 
action,  the  increase  in  the  time  during  which  they  can  re- 
main immerged,  their  increased  speed,  etc.,  is  becoming 

41 


much  greater.  The  small  craft,  useful  against  small  sub- 
marines, will  not  be  sufficient  to  cope  with  the  large  sea- 
going submersibles.  What  succeeded  in  1916  will  not 
succeed  in  1917. 

We  are  facing  the  problem  of  dealing  with  a  different 
class  of  submersibles,  the  veritable  submersible  cruisers. 

We  must  do  something  new,  and  not  content  ourselves 
with  developing  old  systems.  This  war  is  undergoing 
transformations  every  day.  What  can  one  do  against  an 
enemy  that  invents,  or  uses  in  a  masterly  fashion  the  in- 
ventions of  others,  if  one  does  not  also  invent,  and  invent 
more  and  better  than  he.^  To  catch  up  with  Germany  it 
is  not  sufficient  to  take  one  step  in  the  same  time  that  she 
is  taking  one. 

Such  are  the  grave  problems  confronting  ns  today. 
When  all  is  said  and  done,  if  the  appeal  to  invention  proves 
fruitless,  it  should  be  remembered  that  the  masters  of  the 
seas  still  have  at  their  disposal  a  radical  means  of  finishing 
this  submarine  warfare. 

Stirling,  Commander  Yates  (U.  S.  N.) 

The  submarine. — Strategy;  tactics. 

Proc.  U.  S.  Naval  Inst.,  1917,  July,  vol.  4S,  no.  7,  pp. 
1386-89. 

The  following  situation  is  discussed  by  the  author:  Two 
belligerent  naval  powers,  each  with  formidable  surface 
fleets,  holding  them  in  port,  fearing  in  the  case  of  the 
stronger,  the  enemy's  undersea  power  and  in  the  case  of 
the  weaker,  the  enemy's  surface  power.  A  nation  weak  in 
capital  ships  and  therefore  unable  to  maintain  a  threaten- 
ing naval  force  upon  the  flank  of  an  advancing  enemy 
should  be  able  to  rely  upon  an  effective  submarine  offensive. 
With  mobile  types  a  dangerous  sea  area  can  be  made  for  an 
enemy,  when  he  enters  this  area  he  will  be  navigating  in 
the  vicinity  of  numerous  unchartered  rocks — the  subma- 
rines. If  the  weaker  nation  owns  high-speed  battleships, 
capable  of  tracking  an  enemy  fleet  without  being  brought 
under  superior  gun  power,  these  submarines  can  all  be 
concentrated  upon  the  enemy.  Tactics  both  for  offensive 
and  defensive  are  outlined. 

42 


1917— Woodhouse,  H. 

Submarine  hunting  bj  air  craft. 
Flying,  1917,  May,  vol.  6,  no.  4,  pp.  267-273. 
Some  months  before  the  beginning  of  the  great  war,  the 
British  submarine  A-7  was  lost  near  Plymouth,  and  an 
airplane  was  employed,  among  other  means,  to  find  it. 
The  airplane  proved  to  be  the  most  efficient  means  for 
finding  the  submarine.  The  great  war  was  only  a  few 
months  old  when  the  revolutionary  value  of  both  sub- 
marines and  aircraft  became  evident.  As  the  number  of 
both  submarines  and  aircraft  increased,  their  operations 
extended  more  and  more,  and  as  the  submarine  menace 
grew,  the  nations  had  to  meet  it,  and  found  that  the  air- 
craft was  the  best  weapon  for  hunting  submarines.  Sir 
Edward  Carson  reported  that  since  the  commencement  of 
the  war  the  British  navy  had  examined  25,874  ships.  From 
the  beginning  of  the  war  up  to  Oct.  30,  1916,  the  British 
navy  transported  across  the  seas  8,000,000  troops;  9,420,- 
000  tons  of  explosives  and  material;  47,604,000  gallons 
of  gasoline;  over  a  million  of  sick  and  wounded  and  over 
a  million  mules  and  horses.  When  it  became  necessary 
to  build  up  a  system  of  protection  against  submarines, 
the  warring  nations  pressed  into  service  thousands  of  small 
vessels,  destroyers,  trawlers  and  submarine  chasers;  and 
as  fast  as  they  could  obtain  them,  they  put  into  service 
seaplanes  and  dirigibles,  to  cooperate  with  the  ships  in 
locating  and  capturing  and  destroying  hostile  submarines ; 
and  in  convoying  ships,  protecting  them  from  submarine 
attacks. 

The  first  report  of  an  attack  on  submarines  by  an  air- 
craft was  issued  by  the  German  Admiralty  on  May  4, 
1916.  It  stated  that  on  May  3,  a  German  naval  dirigible 
fought  several  British  submarines  in  the  North  Sea  and 
dropped  bombs  on  them,  sinking  one.  The  submarines, 
the  report  stated,  fired  on  the  dirigible  without  success. 
Numerous  other  reports  of  attacks  on  submarines  and 
sinking  of  submarines  were  made  public  in  1916,  mostly 
successes  of  the  Allied  aviators.  The  policy  has  been  to 
capture  the  submarines  whenever  possible.  The  report 
of  one  of  the  latest  cases  is  where  two  submarines  were 

43 


enmeshed  as  the  result  of  the  cooperation  between  aircraft 
and  trawlers.  The  U-boats  were  detected  beneath  the 
surface  by  a  patrol  seaplane.  The  aviator  signaled'' for 
trawlers  and  circled  about,  directing  the  placing  of  nets. 
Soon  these  were  drawn  completely  about  the  unsuspecting 
submersibles,  which  were  brought  to  the  surface.  Hun- 
dreds of  these  aircraft  are  employed  to  cooperate  with 
destroyers,  trawlers  and  submarine  chasers  in  capturing 
or  destroying  hostile  submarines  and  searching  coasts  for 
submarine  bases.  The  usual  evidence  of  the  submarine's 
presence  is  the  wake  of  the  periscope.  This  wake  cannot 
easily  be  seen  from  ships,  but  can  always  be  clearly  seen 
from  airplanes.  For  one  thing,  the  aviator  is  not 
troubled  by  the  reflection  of  the  rays  of  light,  whick 
interferes  with  the  vision  of  the  person  on  a  ship.  The 
aviator,  flying  at  a  height  of  from  1000  to  6000  feet,  has 
a  range  of  vision  of  many  miles,  and  the  whitish  wake  of 
the  periscope  is  clearly  visible  against  the  dark  surface  of 
the  waters,  even  in  cases  where  the  sea  is  fairly  rough  and 
white  caps  are  showing.  In  clear  weather  an  aviator  from 
a  height  of  between  1000  and  3000  feet  can  also  see  a 
submarine  under  water.  In  clear  weather  and  clear  water, 
he  can  see  the  submarine  even  when  it  is  at  a  depth  of  100 
feet.  The  U-53  is  213  feet  3  inches  long,  and  later  ones 
are  even  larger.  Such  submarines  present  a  very  large 
tr^k,  and  whereas  their  speed  submerged  is  between  10 
and  15  knots  at  most,  the  seaplanes,  which  go  at  a  speed  of 
up  to  90  miles  an  hour,  and  even  the  seaplanes,  which 
have  a  speed  of  only  about  35  miles  an  hour,  have  an 
advantage  over  the  submarines.  If  a  submarine  is  seen 
under  water,  the  aircraft,  whether  seaplane  or  dirigible, 
being  equipped  with  wireless,  and  bombs,  first  send  a 
wireless  summoning  destroyers,  trawlers  and  submarine 
chasers.  Whenever  possible  an  opportunity  is  given  to  the 
trawlers  or  the  ships  which  operate  the  nets  to  come  up 
to  the  submarine  and  enmesh  it  in  the  huge  net.  That 
saves  the  submarine,  and  the  crew  is  made  prisoner.  If 
a  submarine  finds  itself  in  danger  and  submerges,  it  leaves 
an  oily  patch,  which  is  clearly  visible  from  the  air,  al- 
though far  less  visible  from  a  ship.     Whereas  the  s«b- 

44 


marine  cannot  launch  a  torpedo  without  getting  its  bear- 
ings, i.  e.,  without  showing  its  periscope  abore  the  water, 
it  should  be  an  easy  matter  for  a  seaplane  to  follow  the 
course  of  a  submerged  submarine  and  attack  it  with  bombs 
at  the  very  moment  the  periscope  pops  out  of  the  water. 
Considering  that  when  a  periscope  shows  the  pilot  has  to 
decide  how  to  act,  and  that  unless  the  aircraft  is  flying 
low,  it  is  hard  to  distinguish  the  features  of  the  submarine 
from  a  height,  one  can  well  understand  why  even  naval 
men  in  different  countries  have  found  it  hard  to  tell 
whether  a  given  submarine  was  one  of  their  own  or  the 
enemy's.  The  only  way  to  prevent  mistakes  and  not  let 
hostile  submarines  get  away  is  for  the  commanders  to  give 
the  aerial  submarine  hunters  information  regarding  the 
movements  of  friendly  submarines  operating  in  the  local- 
ity. Hundreds  of  kite  balloons  have  been  used  as  look- 
outs for  submarines  in  the  great  war.  When  they  see  a 
submarine  or  a  doubtful  ship,  they  summon  the  seaplanes, 
destroyers  and  submarine  chasers  by  wireless.  The  em- 
ployment of  kite  balloons  as  lookouts  releases  dirigibles 
and  ships  from  continuous  patrol  of  different  localities 
which  are  equally  well  protected  through  the  work  of  the 
observers  in  the  kite  balloons. 


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FROM  THE  LIBRARY 
OF 

NEIL  ARTHUR  GETZ 

Inventions  and  suggestions  received  by  the  Naval 
Consulting  Board  are  examined  in  a  preliminary  way 
by  the  Secretary,  who  is  aided  by  the  following  com- 
mittee of  examiners : 

Chables  Messick — Lieutenant  (j.  g.),  U.  S.  N.  R.  F.,  detailed  to  Sec- 
retary's oflSce  Naval  Consulting  Board;  Member  Am.  Inst.  Elec.  Engrs.; 
Patent  Attorney;  developed  and  patented  electrical  hoisting  and  conveying 
machinery;  developed  and  patented  new  methods  in  continuous  casting  of 
soft  metal;  developed  and  patented  the  combined  clutch  and  adjustments 
device  used  on  modern  motorcycles,  etc.,  etc. 

G.  Hebbebt  Condict — Consulting  Engineer;  Member  Am.  Inst.  Elect. 
Engrs.;  Franklin  Inst.;  Member  Executive  Committee,  American  Peat 
Society;  Past  Pres.  N.  Y.  Electrical  Society.  Among  other  activities, 
1896-7,  Genl.  Mgr.  and  Chief  Engr.  Englewood-Chicago  Electric  Ry.; 
1897-1902,  Chief  and  Consulting  Engineer,  Electric  Vehicle  Co.,  New  York 
and  Hartford;  1903-06,  Vice-Pres.  and  Genl.  Mgr.  Electro-Dynamic  Co.  in 
New  York;  1906-09,  Genl.  Mgr.  Box  Electric  Drill  Co. 

Cabl  K.  Mac  Faddex — Technical  advisor  of  companies  interested  in  petro- 
leum; Member  Society  Naval  Architects  and  Marine  Engineers;  Associate 
Member  American  Soc.  Naval  Engineers;  Fuel  Oil  Expert  and  Consulting 
Engineer. 

Chables  E.  Pabsons — Consulting  Engineer;  B.  E.,  Union  College,  1898; 
2nd  Liettt.  Second  New  York  Volunteer  Infantry,  Spanish-American  War; 
Chief  Engineer  Hudson  River  Water  Power  Co.  and  Atlanta  Power  Co., 
1898  to  1913;  President  Ambursen  Construction  Co,  to  1915;  Vice-President 
Deppe  Motors  Corporation;  Member  American  Society  Civil  Engineers; 
Associate  Member  American  Institute  Electrical  Engineers. 

Samuel  E.  Dabby — Patent  Lawyer  and  Expert;  attended  United  States 
Naval  Academy,  1882-86;  Assistant  Examiner  and  Chief  Clerk  U.  S.  Patent 
Office,  1886-94;  Commander,  1901-03,  and  Captain  commanding  Illinois  Naval 
Reserve,  1903-05. 

DoKALD  M.  Bliss — Consulting  Engineer;  Chief  Engineer,  Holtzer-Cabot 
Electric  Co.,  Designer  of  electric  motors  and  special  devices  for  battleships, 
navy  yard  and  coast  defense  apparatus,  direct  and  alternating  current 
motors,  1896-1907;  President,  Engineering  Specialty  Co.,  1908-09;  Chief 
Engineer,  Laboratories  Thomas  A,  Edison,  1910-13;  designed  and  equipped 
Munition  Plant  of  Canadian  Car  &  Foundry  Co.,  1914-15;  Proprietor,  D.  M. 
Bliss  Co.,  New  York. 

GutTATo  L.  Goviir. 


Gkoboz  H.  KnucH. 

Aij^K  T.  BuRixioH,  Office  Manager. 


uc  sou-HtR\  nt 


A     000  892  794     9 
47 


NAVAL  CONSULTING  BOARD 
of  tkt  United  States. 


Addicks,  Lawrence 
Arnold,  Bion  J.,  Lieut.  CoL 
Baekeland,  Dr.  L.  H. 
Brunton,  D.  W. 
Coffin,  Howard  E. 
Craven,  Alfred 
Edison,  Thomas  A. 
Emmet,  William  Le  Roy 
Hunt,  Andrew  Murray 
Hutchison,  Dr.  M.  R. 
Lamme,  B.  G. 
Maxim,  Hudson 

President 

Thomas  A.  Edisoa 
Chairman 

W.  L.  Saunders 


Miller,  Spencer 
Richards,  Prof.  Jos.   W. 
Hiker,  Andrew  L. 
Robins,  Thomas 
Saunders,  W.  L. 
Sellers,  Matthew  BacoB 
Sperry,  Elmer  A. 
Sprague,  Frank  J. 
"rtiayer,  Benjamin  B. 
Webster,  Dr.   A.  Gordo« 
Whitney,  Dr.  W.  R. 
Woodward,  Dr.  Robert  S. 

Vice-Chairman 

Benjamin  B.  Thayer 
Secretary 

Thomas  Robins 


War  Committee  <^  Technical  Societies. 


Harold  W.  Buck 
Dr.  A.  S.  McAllister 

Nelson  P.  Lewis 
Major  Jumes  M.  Boyle 

Arthur  M.  Greene,  Jr. 
R.  N.  Inglis 

D.  W.  Brunton 
Edmund  B.  Kirby 

Joseph  Bijur 

Dr.  Charles  A.  Doremus 

CJhristopher  R.  Coming 
George  C.  Stone 

Lu  B.  Marks 
Preston  S.  Millar 

Dr.  Charles  F.  McKenna 
Frank  K  Dodge 

Henry  Torrance 
F.  E.  Matthews 

Dana  D.  Bamum 

E.  C.  Uhlig 

Lt.  CoL  M.  T.  Bogert 
Dr.  Charles  BaskerriUe 
W.  D.  Richardson 

CnmriJMJii 

D.  W.  Bruntoa 


American  Institute  of  Electrical 
Engineers 

American  Society  of  Ciril 
Engineers 

American  Society  of  Mechfinical 
Engineers 

American  Institute  of  Mining 
Engineers 

American  Electro  Chemical 
Society 

Mining  and  Metallurgical 
Society  of  America 

Illuminating  Engineering 
Society 

American  Institute  of  Chemical 
Engineers 

American  Society  of  Refrigerating 
Engineers 

Americafi  Gas  Institute 


I 


Anerican  diemictd  Society 
|Co-operating) 


Acting  Secretary 
Edmund  B.  Kirby 


